# VentureCraft Go-Dap GD-04 for iPhone 4



## Randius

The next iteration of Go-Dap specifically designed for the iPhone 4 is now announced at CES. Still about twice as thick and now it seems that all the buttons and indicators are shifted to the left side. There is also a button for selecting the sampling rate/gain at 48k and 96k/24bit when output the signal through the optical. 
   

   

   

   
  This is still pretty much a prototype and hopefully the production unit will be thinner when releasing in April.


----------



## Trisk3lion

My first thought was, this thing is big. But then you consider how much futures it packs: DAC, Amp and a battery, then it feels very resonible. 
I'm definatly going to have my eyes open for this one when it comes out!


----------



## arnaud

Posted originally in another thread - spring headphone festival from Fujiya Avic in Tokyo (http://www.head-fi.org/forum/thread/548917/headphone-festival-2011-in-tokyo-may-7th-2011#post_7457238): 
   
  Listened to go-dap 4 prototype for iphone4, the design is really cool but apart from tightening up the bass with my iem (Sensaphonics 2-XS), there wasn't sufficient gain in SQ to justify the added weight / size. I even thought it might be a tad too warm sounding for my already quite dark sounding iems... The price sounds about right (35,000JPY) and it includes SPDIF optical out so you can use it as a transport. It works at 48 or 96kHz, 16 or 24 bits. I assume it can read 96/24 stream from the ipod.


----------



## tds101

Any news on the availability of this beauty???


----------



## Randius

Quote: 





tds101 said:


> Any news on the availability of this beauty???


 

 It is scheduled to be available in June and MSRP is about.... 430USD


----------



## PXSS

It's unclear to me if this re-digitalizes the music to the digital out or is it straight digital out from the iPhone like the CLAS?


----------



## qusp

when is someone going to release something that is just a transport, rather than including a heap of features that many that want high end sound will simply bypass and pay for for no reason


----------



## MorbidToaster

There's some weird stuff going on here, but I LOVE the idea...It looks great.


----------



## gkanai

Is this product out yet? The website of the company is only promoting the 3GS model.


----------



## DAPVentureCraft

Hello.
   
  We apologize not to inform you about the progress on our new model for iPhone4 for such a long time.
  Since we are not in a sponsor at Head-Fi currently we would like to make an announcement about our latest model here instead of Sponsor Announcement and Deals.
   
  We are still working on developing our new model, Go-Dap Unit4.0 (previously named GD-04) and its official release for a market would be likely this summer in fact.
  The spec of Unit4.0 would be changed from the specs that we informed you before at the exhibition at CES and our promotion video.
  The latest spec will be as attached catalog below.
   
   

   
   
  Dimensions---------
  Width: 63.40mm
  Height: 127.75mm (main unit)
  Depth: 23.00mm
  Weight: 139g
   
   
  Technical specifications---------
  Battery: lithium-ion
  Capacity: 1580mA/h
  S/N ratio: 95dB or more
  Charging method: USB cable (USB 2.0) (included)
  Maximum output: 50mW + 50mW (32Ω)
  Distortion rate: 0.009%(10mW)
  Frequency characteristics: 20-20kHz
  Adaptive impedance: 16Ω or higher
  Output terminal : 3.5mm headphone jack
                        : 3.5mm toslink digital output
   
   
  We just exhibited some trail pieces at Fujiya Aciv Headphone Festival in May in Tokyo and hold a demonstration to the visitors which only ended up showing mock-ups at CES 2011 at Las Vegas.
   
  VentureCraft table at Fujiya Avic Headphone Fes in Tokyo
https://picasaweb.google.com/takano.hanae/Unit40DemoAtFujiyaAvicInTokyo?authkey=Gv1sRgCOrqpv6r6rXgbg#
   
   
  We are going to exhibit the Unit4.0 at CE Week Line Show at NYC at 22-23 of June and hopefully we can do some demos there as well.
  VentureCraft Table No: T41
http://cealineshows.com/
  Drop our table and try our Unit4.0 with your iPhone4 if you have a change to come over to NYC during the above period.
   
   
  The price for the Unit4.0 will be decided later.
  We will renewal our website along with the official release of the Unit4.0 and you will be able to purchase the item through our website firstly.
   
  Please give us a little more time to finalize our high-spec model and wait till we make an announcement at our twitter, website, Head-Fi or Jaben around this summer.
   
   
  Thank you for your support,
   
   
  VentureCraft
http://venturecraft.jp/gadget_en/
http://twitter.com/#!/DAPVentureCraft
  http://www.youtube.com/watch?v=wYNIBcpyOA4


----------



## Jonasklam

Quote:


> VentureCraft
> http://venturecraft.jp/gadget_en/
> http://twitter.com/#!/DAPVentureCraft
> http://www.youtube.com/watch?v=wYNIBcpyOA4


 
   
  Nice...
   
  Though, LOLOLOOL at that promotion video!  haha


----------



## MorbidToaster

I'm really interested in this product still. If you can make it sound great, and charge my phone too, I'll love it. 
   
  I've been interested in a charging case for quite awhile, and this would be perfect if it sounds good.


----------



## mopiko

retail price?


----------



## tds101

I want this so bad!!!


----------



## zzffnn

Very interested. Please advise me on the following questions:
  1) Is this unit only for iPhone 4? Not for 3gs, 4th and 3rd Gen iPod Touch, and iPad?
  2) Does the headphone output take the analog signal from the dac of Go-dap or from the dac of iPhone?
  3) what are the dac chip and the opamps?
  Thanks.


----------



## qusp

i do wonder about the hires capability and whether it can be switched off, iphone isnt capable of playing hires without crack and i'm not sure even then if it upsamples. so i suggest you just keep the high spec model bit-perfect rather than upsample so the spec reads well. i would also rather spdif on coax than optical


----------



## Jonasklam

Quote: 





zzffnn said:


> Very interested. Please advise me on the following questions:
> 1) Is this unit only for iPhone 4? Not for 3gs, 4th and 3rd Gen iPod Touch, and iPad?
> 2) Does the headphone output take the analog signal from the dac of Go-dap or from the dac of iPhone?
> 3) what are the dac chip and the opamps?
> Thanks.


 


  1) I am pretty sure this doesn't support the 3GS/3G (but afaik, they have made an earlier version for these iPhones)
  2) Donno, but but would guess DAC of the iPhone
  3) Donno either


----------



## Crenshaw

I'm slightly confused. the iphone doest play anything above alac 44khz/8bit, so how is the go dap playing 48khz/16bit?


----------



## zzffnn

Thanks Jonasklam,
   
  I should have specifically ask VentureCraft / Go-dap to answer my questions. We are speculating after all (I would guess the same as you said but that is just speculation). I think only VentureCraft / Go-dap can answer these questions. Thanks.
  
  Quote: 





jonasklam said:


> 1) I am pretty sure this doesn't support the 3GS/3G (but afaik, they have made an earlier version for these iPhones)
> 2) Donno, but but would guess DAC of the iPhone
> 3) Donno either


 

 Originally Posted by *zzffnn* 


  
  Very interested. Please advise me on the following questions:
  1) Is this unit only for iPhone 4? Not for 3gs, 4th and 3rd Gen iPod Touch, and iPad?
  2) Does the headphone output take the analog signal from the dac of Go-dap or from the dac of iPhone?
  3) what are the dac chip and the opamps?
  Thanks.


----------



## DAPVentureCraft

Hi, everyone!
   
  To answer your questions
   
  1. Unit4.0 is only for iPhone4.
   
  2. Unit4.0 receives digital signal from iPhone4 and convert the digital signal to the analog signal through the DAC (Analog-to-Digital Converter) loaded on the device, then outputs analog signals to a headphone/earphone by amplifying the signal with a headphone amp.
   
  3. DAC Chip: AKM http://www.asahi-kasei.co.jp/akm/en/product/
      Ope-Amp: Burr-Brown http://www.burr-brown.com/
   
  4. Unit4.0 decodes the digital data in several formats coming from iPhone4 into PCM format.
  A sampling rate convertor loaded on Unit4.0 changes frequency response as all in 48kHz within the decoder then the DAC converts 48kHz/16bit into analog signals.
   
Thanks!
   
VentureCraft


----------



## qusp

erm DAPVenturecraft, i think you should realize that this forum is probably a bit more savvy than your average forum. telling us that the dac is made by akm and the opamp is made by burr brown/texas instruments, tells me nothing. both companies make nice sounding, appropriate products and stuff that sounds like utter poo.
   
  when asked here what dac and opamp, its a specific question of what model dac chip and what model opamp. is the dac chip a ladder dac, sigma delta dac, 32 bit dac, upsampling or non oversampling. is the opamp a fet input opamp with unity gain buffer, or bipolar input opamp. is the digital transfer from iphone asynchronous or isochronous endpoint etc etc.
   
  ok so thats probably a bit more technical than the average user here, but there will be some that want to know more and even those who dont really understand will want to know the details so they can go and get the research done so they do understand


----------



## zzffnn

You are a tough man, qusp. But that was exactly what I wanted to know.
   
  Yes, specific dac / amp model please. Vendors here usually disclose those specs as selling points. If there is anything fancy inside, this forum is the place to reveal it.
   
  edit for typos.


----------



## qusp

hehe wasnt meant to be harsh, just real feedback. I also didnt expect you to furnish me with answers to all those specs, although we both know quality sound is all in the implementation of the chips. the opamp model and dac chip assignment shouldnt give away anything of your design and even then depending on the implementation, that doesnt say much either. both companies have massive catalogues, thats all. its an intriguing product and i'll keep my eye on it for transport duties.


----------



## DAPVentureCraft

Some updates about Go-Dap Unit4.0
http://www.facebook.com/profile.php?id=100002574314835


----------



## DAPVentureCraft

Go-Dap Unit4.0 Review by Stapa Saito. Only available in Japanese.
  - Watch http://k-tai.impress.co.jp/docs/column/stapa/20111003_481296.html via


----------



## Randius

At least now we know what DAC and OPAMP the GD-04 is using.

DAC - AKM AK4353
OPAMP - JRC MUSES8820E

Hmm... the headphone out is also the optical output...


----------



## Kodan420

Is the Go-DAP 4.0 available in the US yet and if so what is the cost and how do we order? I was VERY VERY pleased with Go-DAP for my Iphone 3GS and now that I am ordering a 4S I would love to have some info on how to purchase one of these for the new phone. Thanks.


----------



## obazavil

Did they mention the ETA for availability in the US before?


----------



## AnakChan

Hmmmm...I've had my Go-DAP for about 4 days now and when I bought it I had to sign a form to say I'm testing and have to provide feedback. Now that iOS5 is out (and I've heard problems of iOS5 with CLAS), I'm assuming the Go-DAP & HP-P1 will have the same problems. Chances are these will probably have to be fixed before going for an international release.


----------



## obazavil

Is final design, or they will still change the prototype?
   
  That volume knob seems to big in the pictures.
   
  So far, how it compares against hp-p1?
  Quote: 





anakchan said:


> Hmmmm...I've had my Go-DAP for about 4 days now and when I bought it I had to sign a form to say I'm testing and have to provide feedback. Now that iOS5 is out (and I've heard problems of iOS5 with CLAS), I'm assuming the Go-DAP & HP-P1 will have the same problems. Chances are these will probably have to be fixed before going for an international release.


----------



## AnakChan

I believe it's the final design physically. I'm guessing if they're sending me a survey form if there's any changes it'll most likely be firmware changes instead. The firmware is still at 1.0 only. I must say that at least with my JVC/Victor HA-FX700 I'm hard pressed to find a discernible difference. Maybe ever so slightly more revealing whereas the P1 a little more "airy". This was more apparent on classical music than say with Jazz. And with Hip-Hop, I couldn't tell a difference at all. Sorry about my terminology, I'm still trying to learn the jargon.
   
  I may be able to provide a better review when I get my UM SE530x8 back from repair.
   
  Huge knob!? Seen the HP-P1 knob instead!?


----------



## Randius

@anakchan: You mean you can hear very little between the P1 and GD-04?
   
  I am waiting to get my hands on one but Hana said it will only be available for oversea likely around November. What is available in Japan now are sample units. GD-04 is not even for sale on their website in Japan.


----------



## moodyrn

If my eyes are not deceiving me, the godap/iphone stack looks to be around the same thickness as the fostex alone. So you a dap, dac, and amp that's about the same size a a bigger sized portable amp? That's very encouraging. I figure the fostex probably sounds quiet a bit better, but I've been waiting on a completely portable solution for an idevice. And not something that's mere transportable. If this sounds significantly better than just an iphone or more yet, an iphone with a decent amp, then this unit with it's size could be a huge breakthrough IMO. And even if the built in amp on the godap is crap, at the very least it does provide a digital signal from idevices and the possibilities with other dac/amp combos are endless.  With the size of the godap/iphone combo, it could still be fairly portable.


----------



## mannn

this sounds good and all ... but iphone 4 has been out for a year... and the form factor is going to change with iphone 5...  which presumably will come out in a year or so (gauging from 3Gs to 4 it was a year)
  and now they are still selling prototype... what happens when i upgrade iphone 5?  this thing will be useless... as far as i can tell this is for iphone 4 only and i can't even put my ipod touch on it if i want to...


----------



## AnakChan

FYI iOS5 and 4S works fine in the Go-DAP. The vibrate window is just a little too high for the 4S but it's not a big deal, you still have access to the switch.
   
  @mann, I can get my GF to talk to Venturecraft as my Japanese is cr@p however in my very loose conversation with the salesguy, I -THINK- Venturecraft can update customer's Go-DAP for changes to the iPhone (e.g. 4S, but I don't know about 5 next year). It seems that the housing is held by 4 screws anyway. I don't know if they intend for customers to do themselves or ship it back in.


----------



## crumpler

Quote: 





dapventurecraft said:


> Go-Dap Unit4.0 Review by Stapa Saito. Only available in Japanese.
> - Watch http://k-tai.impress.co.jp/docs/column/stapa/20111003_481296.html via


 


  Any idea where i might be able to purchase this domestically in Japan? Would appreciate an address or website if possible.


----------



## AnakChan

e-earphone in Akihabara. Approx Y29,800. You also have to sign a piece of paper that you're monitoring and will evaluate the device to get it at that price (RRP is Y35,000).
   
  http://www.e-earphone.jp (don't bother trying to find the 4.0 on the web though, they don't list it there. You have to go to their Akiba store).


----------



## crumpler

Quote: 





anakchan said:


> e-earphone in Akihabara. Approx Y29,800. You also have to sign a piece of paper that you're monitoring and will evaluate the device to get it at that price (RRP is Y35,000).
> 
> http://www.e-earphone.jp (don't bother trying to find the 4.0 on the web though, they don't list it there. You have to go to their Akiba store).


 


  Thanks for that mate. Just google-mapped the place. Can't wait to get a closer look at the 4.0


----------



## AnakChan

I have to warn you, not a place for gear-holics. "you can check out anytime you like, but you can never leave." is never more applicable than here. I actually stayed till they kicked me out 2 weekends ago.


----------



## crumpler

Quote: 





anakchan said:


> I have to warn you, not a place for gear-holics. "you can check out anytime you like, but you can never leave." is never more applicable than here. I actually stayed till they kicked me out 2 weekends ago.


 







 Duly noted!


----------



## AnakChan

@crumpler, after you pick yours up, please let me know what you think about battery life. I think you & I are the only ones (in this forum) who have one. I find the battery life to be short (in terms or charging and using).


----------



## crumpler

Quote: 





anakchan said:


> @crumpler, after you pick yours up, please let me know what you think about battery life. I think you & I are the only ones (in this forum) who have one. I find the battery life to be short (in terms or charging and using).


 


  Wow really? Is it really just you for now? I'm surprised this has taken as long as it has to be launched, i mean after all, the iPhone4 is 15months old!
   
  I'll chime in if/when i get my hands on these.
   
  Just to be clear, how long exactly is the charging or using cycle?


----------



## AnakChan

I'll give it a shot again but last Friday whilst lining up for the 4S, I think the Go-Dap charged my 4 only up to 48% and I really wasn't listening to music much. The charging takes about 5 hrs or thereabouts. As for use, not certain since it charges the phone whilst playing. I'll give it a test tomorrow.
   
Semi-Review Time
  One gripe...why can't it charge the unit, the iPhone, & use it simultaneously!? When you have the USB plugged in it charges the Go-DAP in Amp and Amp-i mode. But enables Sync to iTunes in Sync/Off mode (charges the iPhone, but not the Go-DAP). To use the DAC/Amp, you'll need to disconnect the USB cable. Off/Sync with the USB disconnected just means off - no charging or anything. Amp mode means using the DAC/Amp and the battery is dedicated to the DAC/Amp function (no iPhone charging). And finally Amp-i mode means using DAC/Amp and the battery is used for both DAC/Amp and for iPhone charging.
   
  Once the battery is drained, the DAC/Amp stops to function (i.e. cannot use the iPhone as a power source - just like other DAC/Amps).
   
_Note: with the latest iPhone 4s (or iOS5 feature?) if wireless sync is enabled, you can sync to iTunes in both Sync/Off mode with the USB cable plugged in. Or with the USB cable disconnected and the Go-DAP in Amp-i mode._
   
  Also (not that it's such a big deal) but the unit will always operate as a DAC/Amp. I don't believe there's a toggle to use it as an Amp only (and take line-out from the base). Initially I thought that was the difference between Amp & Amp-I; that Amp was using the iPhone DAC, and Amp-I was using the Go-DAP as a DAC/Amp. But it seems Amp just means you're not charging your iPhone and the battery is used exclusively for the DAC/Amp. Whereas in Amp-I, the battery is used for both DAC/Amp and for charging the iPhone.
   
  Edit #1: I just played around with the ASR function and (as sad as it sounds for an audiophile-wannabe), I like it...seems to bring the mids more forward. To try to be smart (but could be using the wrong terminology altogether) it seems to "remove the veil" in the mids. It's meant to (in it's own words) "take a compressed audio source and reproduce it in high quality Hi-Fi sound that is close to the audio source". But in my primitive opinion it's some sort of preset equaliser setting 'cos it alters even my ALAC (though compressed shouldn't have any loss, right?).
   
  BTW, came across this advertising site which gives more info on the Go-DAP in English, I don't recall seeing this site before.
  http://go-dap.com
   
  Edit #2: Go-DAP in Amp mode (i.e not charging the iPhone) lasts 7 hrs 40 mins of continuous use.
   
  Further Go-DAP info can be found below note information may be in Japanese :-


  Twitter: http://twitter.com/#!/DAPVentureCraft
  Facebook: http://www.facebook.com/pages/VentureCraft/225114777548206?sk=wall
  YouTube: http://www.youtube.com/user/DAPVentureCraft
  Flickr: http://www.flickr.com/photos/64611829@N03/sets/
   
  e☆Earphone TV at USTREAM on Oct 27 2011
http://www.ustream.tv/recorded/18139580


----------



## takoyaki

The another model was released.
  OPAMP was changed to OPA2134, I like new one.
  (left:OPA2134 model, right:MUSES8820 model)


----------



## TnTMaN

I own both the iFuzen and the GoDap 4.0..
   
  Both have their cons and weaknesses..
   
  The iFuzen has a few bugs where it might freeze up every once in a while or sometimes the iPhone might not detect it and you have to power cycle it. Other than that the sound quality is quite awesome. I am using this with my Ortofon e-Q5 and Audio Technica ES10.
   
  On the e-Q5, the soundstage is emersive, bass is very well controlled. It brings the mids a little forward, but opens up the  width. Listening to a track from Olivia Ong's live concert her voice really airs out... very impresssed. the iFuzen is bested used in the right side of the headphone plug in the 1 flash setting. 
   
  The ES10 is quite a bass heavy can, the highs can be a bit shrilling at times thus closing off the mids a bit. However with the iFuzen the bass gains a significant increase in control. Bass lines on Jesse J's Price Tag have so much speed and depth now. The slams are real slams, not woofs. 2 thumbs up in this department.  Needless to say the amp opens up the sound stage and actually tames the high shrills. I listened to some acoustic guitar tracks and  whilst it used to sound dull, the picks of each string are crisp and not fatiguing to listening to on a longer listen session.  
   
  I am very impressed with iFuzen, It's got variable sound settings that allow you to taylor the sound to each different can or headphone. 
   
  The GoDap 4.0 on the other hand is not as versatile or compatible with different cans.
   
  It works well with my ES10, it controls bass very well even better than the iFuzen. The mids really open up a tad more than the iFuzen, but the real star is the highs. It brings out every minute detail there is. Suddenly my ES10 are like Stax electrostatics!  (well not really.. but imo close!)
   
  Their is a problem with the GoDap 4.0, it's crap with my e-5Q!!!! The e-5Q are high sensitive earphones, as it is not a bassy earphone the GoDap actually reduced the bass to almost nothing. It is very thin and almost like it took the bass away. The mids were are right in your face, and the highs shrivelled badly in my ear. I can't use the GoDap with my e-5Q!  Made it sound like iphone headphones.....
   
  Overall, my favorite pairing is:  iFuzen with e-5Q and GoDap 4.0 with ES10.
   
  Fire any questions you might have!


----------



## AnakChan

FYI: The Go-DAP actually has a version upgrade from 1.01 to 1.02. The minor revision is merely to change the rate of volume increase. As I understanding it, instead of a linear increase (from the rotation or the volume knob) it increases more exponentially. I should be getting my Go-DAP back from VentureCraft tomorrow.


----------



## qusp

cool, nothing stopping us changing opa2134 to opa1642 or other suitable soic8 unity gain stable opamp. the opa2134 is ok, nothing wrong with it per say, but i certainly have other preferences and since its a simple soic8 chip it will be easy to change out.


----------



## moodyrn

Does the ifuzen take a digital signal from the iphone like the godap does, or does it take the signal from the line out and uses the iphone's internal dac?


----------



## takoyaki

It is firmware information of my godaps.
  Left: MUSES8820 updated firmware, Right: OPA2134 initial firmware.


----------



## AnakChan

@takoyaki, do you have both Muse & Burr Brown versions? Do you hear any differences??


----------



## takoyaki

Quote: 





anakchan said:


> @takoyaki, do you have both Muse & Burr Brown versions? Do you hear any differences??


 
   
   
  The OPA2134 version has the quantity of a high and low than an MUSES8820 version.
  I like OPA2134 version.


----------



## AnakChan

@takoyaki, wait I'm a little confused. As you can see pix from my earlier posts I have the Go-DAP with the red front plate. So that should be the Muse version.

But as you can see from my earlier post here, http://www.head-fi.org/t/533084/venturecraft-go-dap-gd-04-for-iphone-4/30#post_7818738, my Go-DAP says GD-04LI.

Is it definitive that :-

GD4 == Muse 8820
GD-04LI == OPA2134??


----------



## takoyaki

Quote: 





anakchan said:


> Is it definitive that :-
> 
> GD4 == Muse 8820
> GD-04LI == OPA2134??


 
   
  Yes.
  My MUSES8820 version is initial release of GoDap unit 4.0.
  There is two version, perhaps.


----------



## AnakChan

FYI:
   
  http://www.venturecraft.jp/gadget_jp/index.php
   
  So Go-DAP has another revision update to v1.04. This apparently fixes battery charging issues with the iPhone 4S.


----------



## AnakChan

So a week ago, VentureCraft further announced upgrades and customisable options available to the Go-DAP 4.0. Bear with me that I'm going to regurgitate what they have told me about the upgrades and have not put -my- opinion of the validity of what they've told me.
   
  The upgrades VentureCraft has provided include :-
   
  1) DAC upgrade - adding MUSE F95 capacitor
  2) Gain change - RK73. This seems to change the entire volume range downwards. i.e. if you're used to listening to a particular volume, now you have to turn it up to match the volume you're used to. The explanation I've been told is that by "turning up" that volume it "opens up the DAC" and therefore provides higher bitrate. (this is the disclaimer where I did not question what they said 'cos my knowledge of electronics is extremely basic).
  3) Amp upgrade: 3 options :-
     a) OP-275 - more natural
     b) AD8397 - bipolar, suited for Jazz, female vocals, classical
     c) OPA-2604 - classic FET, supposedly better for electronic/type music
   
  As mentioned, I'm regurgitating what I was told (pls bear in mind I'm listening to Japanese-translated English - it's possible that it could be described entirely differently).
   
  What I have done is to upgrade both my Muses 8820 and BurrBrown OPA2134 to OPA-275 and AD8397 respectively. I also did the DAC and the Gain upgrades. For the past week I've been demo-ing between the two. The upgrades definitely improve the SQ of the Go-DAP for both. I found that the AD8397 was good for the bebop jazz I like and has a slightly wider soundstage than the OP-275 amp. The highs seem more revealing -a little more- than the OP-275.

 The update to me narrows the gap difference between the original Go-DAP 4.0 (Muses 8820/BurrBrown OPA2134) and the Fostex HP-P1, and seriously challenges it in fact. In addition that the Go-DAP 4.0 upgrade puts your iPhone into a convenient portable package, if I'm travelling I'd rather carry the Go-DAP over the Fostex HP-P1 cos the difference (to my ears) is negligible.
   
  However in terms of VentureCraft as a business and the Go-DAP as a project, I think there is much room for improvement.
  
  1) the jacket needs to be modular and swappable in case the iPhone 5 has a different form factor. VentureCraft has a good DAC/Amp product but the lack of modularity is a major disappointment. No one is going to spend $600 for a device that lasts as long as your iPhone 4/4S (Apple upgrades every year!).
  2) They have got the sound right -NOW- with these upgrades and customs. That means early adopters of Go-DAP 4.0 Muses 8820 and BurrBrown OPA2134 pretty much lucked out. The gain and the DAC upgrade should have been standard instead of upgrades. The only real custom is the differences in the 3 Amp options.
 3) As a business I think they need to reconsider their marketing and product release strategy. The Go-DAP 4.0 in its earlier form seemed "rushed" out of the market. Yet it's released late (1 year after the iPhone 4 was released). At least in my opinion they should have :-
    a) held back the Go-DAP 4.0, got the design more tuned to what is is now with the DAC/gain/Amp upgrades as standard into the product
    b) designed something more modular (c'mon, they had the 3G/S version and now repeating the same mistake for the 4/S?). Think of the Hifiman DAPs that have modular amps. And of course the iPhone 4 jacket needs to be modular and replaceable.
     c) get the two above right then come up with something good that is released in conjunction with the iPhone 5 next year.
     d) have the firmware user self-upgradeable (this is a problem for -all- iDevice DAC makers: Fostex, Cyperlabs, and VentureCraft)
   
  Info about the upgrades are here (in Japanese). They're not cheap...the Go-DAP 4.0 is currently going for USD$448 (this month special USD$384). The complete upgrades (DAC/Gain/Amp) are a further USD$228 :-

 http://item.rakuten.co.jp/japanshop/c/0000000108/


----------



## AnakChan

[Snip] Apologies, information not ready.


----------



## ST03

Wow, that's fantastic. I suppose I'll keep my iphone as a DAP when I get the iphone 5 next year. Best dealer for the GoDap that ships to the USA?


----------



## AnakChan

[Snip!] Apologies, information not ready.


----------



## AnakChan

*Go-DAP 4.0 OpAmp Comparison Review*
   
*Brief History*
  For the past few weeks I've had a couple of Go-DAP 4.0s on loan for a review. Some of you may know that in the past 6-7 months I've had bought a couple of Go-DAPs, upgraded them, then got rid of one. I started off with the Muses 8820E first back in early October and very soon after the BurrBrown OPA2134. Then VentureCraft announced they were providing upgrades to the OpAmps offering 3 versions, OP-275, AD8397, and OPA-2604. I upgraded one Go-DAP to the OP-275, and another to the AD8397.
   
  Since then, VentureCraft has offered another OpAmp, not as an upgrade but as it's own Unit 4.0 - the OPA1612.
   
  I kept my AD8397, sold the OP-275 to a friend and for the past few months the Go-DAP 4.0 AD8397 has been my favourite portable DAP.
   
*Current Go-DAP Comparisons*
   
  I've talked about my AD8397 in the past in some Go-DAP threads so I won't be talking about this OpAmp. However I have managed to secure the original Muses 8820 & the OPA1612 on loan from VentureCraft and this review is specifically about these two models.
   
  Aside from the aforementioned Go-DAPs, my tests involve using the Ultrasone Edition 8's , Unique Melody Merlin's, and V-Moda M-80's. My audio files are a mixture of 256k AAC, 320k AAC, ALAC, and FLAC (via FLACPlayer). My tracks used are Phantom of the Opera, Gerry Mulligan's Night Lights, Paul Desmond's Bossa Antigua, Black Eyed Peas' E.N.D., & Michael Buble's Call Me Irresponsible.
   
   
  Note that all the Unit 4.0 Go-DAPs use the AKM AK4353 DAC so the comparison is primarily on the OpAmp.
   
   
  In general, if one is looking for a completely integrated DAC/Amp to the iPhone 4S, in my humble opinion, nothing beats the Go-DAP. I know many Head-fiers have concerns that the integrated iPhone 4(S) jacket is limiting especially Apple comes up with new iPhone models annually. However if most people buy the iPhones on contract, usually the contract is 2 years so one could get a 2 yrs life out of the Go-DAP. In addition, one could always buy a iPod extended cable and hook up any iDevice to the Go-DAP.
   




   
  Here are the notes I've written up when comparingthe OPA1612 with the Muses 8820E

 Probably the most prominent difference between the two is the 1612 seem to have more depth and more full bodied (apologies if I'm using wine jargon in my comparisons here)
 The 1612 also lean towards a more 3-dimensional soundstage over the 8820E. That's not to say that the 8820E doesn't have much soundstage as it's reasonably wide however the 1612 seems to add depth to the width. The 8820E seems more "flat".
 Across the frequency range, the 1612 seems to have more impact. It's not necessarily "in your face" but whether it's primary vocals, or instruments seem to have more distinction.
 Along with the impact (and probably the cause of the impact) is the 1612 is somewhat more detailed and clear
 Both the 1612 and the 8820E have a wide soundstage however the 1612 has a slight edge over the 8820E.
 The 1612 also has (ever so slightly) an edge over the 8820 in terms of treble extension. At times the 1612 could sound more "bright" and for headphones like the Ultrasone Edition 8's, one may find it fatiguing. The 8820 may be better for such headphones for extended play.
 The 1612's mid bass seems seems more forward too than the 8820. In terms of bass extension though, I think both are the same. At least to me they are full enough with the Merlins and with the M-80's.
   
  Overall, I feel that the 8820E is fine for extended listening to music and seems suited across all genre. Whereas the 1612, I find myself _immersed_ into the music.
   
*Other Aspects of the Go-DAP*
   

 I found the gain settings on the Muses 8820E to have a bigger difference (between low and high) than the OPA1612.
 The 1580mAh battery charges a dead iPhone 4(s) up to about 54% before it kaputs. But very strangely the 2000mAh (the one that comes with the OPA1612) doesn't charge the iPhone 4(s) fully either. I got as high as 68% before the 2000mAh battery went flat. The charging is probably a little too quick...both cases of the 1580mAh and the 2000mAh, it drains in less than 1 hr. This is without using the Go-DAP for music.
 The Go-DAP is reasonably pocketable...it is large however, it is integrated. Carrying something like the HP-P1, or CLAS+Amp is definitely less pocketable.
 The brushed aluminium back scratches very easily. So one has to be very careful with it.
 The Go-DAP can be used as a transport too with an optical out. I've chained up the Go-DAP to my Benchmark DAC1 Pre but to me it sounds flat in comparison to optical out from my iMac or iBasso DX100. Talking to the makers, the Go-DAP apparently up-samples from 44.1kHz to 48kHz and this is a side-effect of the up-sampling. I have not yet tried loading up a 48kHz ALAC/AAC to see if this flatness disappears since no up-sampling is required then. I'll try that later.
   
*Go-DAP vs other iDevice DAC/Amps*
   
  I have actually owned the Fostex HP-P1, CLAS, Pico Slim, and RSA SR-71B. In my honest opinion, the Go-DAP is up there with the rest of them and in my personal opinion I'd lean towards the Go-DAP even for SQ alone. I feel it has a slight edge over both the HP-P1 and the CLAS in terms of detail and whichever OpAmp is chosen they seem to provide a decent amount of bass and treble extension.
   
_NB: Based on memory from last year, the OP-275 on the other hand doesn't seem to have the same treble extension as the AD8397, or OPA1612._
   
  As a complete integrated DAC/Amp package for the iPhone 4(s), the Go-DAP 4.0 is the only product I know. All others are either separate component attachments, or Amp-only integrated package (iFuzen for example).
   

   
  Venturecraft does ship the basic Go-DAP 4.0 model overseas from their online site :-
   
  http://venturecraft.jp/gadget_en/index.php
   
  However if you're looking at the customised versions like the ones mentioned above, the  details are at the bottom of the home page and you'll need to mail VentureCraft on the customisations you require. They will have to give you a mail quote.


----------



## tds101

Any way to get this in the USA???


----------



## AnakChan

They already do ship it there...I don't think wer'e supposed to post links up here so I'm pm-ing you.


----------



## tds101

You are allowed to post links,...as your not the company representative. Quite a few people really want this,...


----------



## AnakChan

Apologies for the delay, you're right - I confirmed with the mods.

The basic Go-DAP can be ordered online & delivered overseas (as far as I know, any country??).

Their page is :-

http://venturecraft.jp/gadget_en/index.php

Note that the homepage contains information about the Unit 4.0 upgrades, not in the Unit 4.0 link instead. As mentioned above you can order the base model from online but if you're requiring upgrades, you'll need to mail them for a custom quote.

I'll put this info into the review page when I get home later tonight.


----------



## tds101

anakchan said:


> Apologies for the delay, you're right - I confirmed with the mods.
> 
> The basic Go-DAP can be ordered online & delivered overseas (as far as I know, any country??).
> 
> ...



Thank you!!! I'm sure everyone here will be quite pleased with information - myself included.


----------



## moodyrn

I'm really shocked to see this thing not getting more attention here. I would have already jumped on it, if I wasn't already committed to getting the iphone 5 later this year. But if he also comes out with an iphone 5 version, I'll be all over it. This product is something people been asking for awhile...a direct lower price competitor to the clas and fostex. I know it's made to fit in an iphone, but you can get a idevice cable with a female end to still use with this. Or am I missing something?


----------



## AnakChan

Yes you can use an iPod extension cable with it. I mentioned it in a different thread a few months back...I should have shared that info here too :-

http://www.head-fi.org/t/597705/portable-rig-for-iphone-4s#post_8181717

You're right that the Go-DAP should really be getting more attention overseas. With the local Japan hifi shows (Tokyo Headphone Festival, Tokyo Heaphone Amp Festival, Osaka Headphone Festival, the VentureCraft guys are there to show their products. they did go to CES to show the Go-DAP there too (one of Jude's CES reviews on YouTube) but I think VentureCaft needs to show some presence to some dedicated audio shows overseas too rather than something big like CES where their products can get overshadowed by many of the other big fancy names there.

If they have the likes of InnerFidelity or (who else are the other headphone/amp/DAC/DAP reviewers??), I think they'll get a lot more coverage. Also letting some of the end user consumers (e.g. Big name Head-Fi members) demo & write reviews would help improve the coverage. Now some audio manufacturers & big names who are in the business of audio have had the opportunity to demo the Go-DAP but they're not writing reviews. I just happen to go through a phase where I bought every portable iDevice DAC/Amp and came across the Go-DAP and was very happy with it.

After purchasing 2xGo-DAPs and upgrading both did I talk to VentureCraft more and recently got the additional Go-DAPs on loan to review. I can check with them but I think I'm th only end consumer given that privilege. I'll talk to them and encourage them to have more end consumers demo their offerings. Would be nice to see if someone else would challenge or agree with my review.

P.S. it appears though locally in Japan, their sales seems to be pretty good at least in the shops. I don't know about online sales. So if it gets popular overseas, I'd be curious if they can handle the volume.


----------



## shotgunshane

Ah, a Head-Fi demo tour would be awesome.
   
  I would be all over this if it were modular, so I could just buy the updated case when the new iPhone comes out, instead of a completely new unit and allowing you to more gracefully use it with an iPad and iPod.


----------



## Javierelizondo

I will be attending the Village Headphone Meet in L.A. on Sunday, April22 2012, and bring with me the new white GO-DAP 4.0, which I haven't been able to turn on because my Senns HD700 haven't been shipped out and my other phones Sennheiser's TR180's are wireless and cannot do an amplifier.


----------



## shigzeo

I've got a loaner from VentureCraft - thank you. 
   
  It is great. Remember, I reviewed the first unit, the one built for the iPhone 3G/S and loved it. The new unit is much better - toslink optical out, better protective case, better selection of upgradeable components (pricey though), easier to access gain and reset switches and some new mode called ASR that is supposed to help expand the highs for lossy music. I'm not one for psychoacoustics, so I'll leave that for you boffins. 
   
  Suffice it to say, I'll be queuing up at the Tokyo headphone show to get one. I love that it does sport everything all in one. I also own the CLAS and National - overall a more powerful system, but one that is more than twice the bulk. Remember, the GoDap works with every iPod that has a 30-pin, at least since 2004. I used four today already with it and my iPhone 4s. It burns through battery at the rate of about 8-9 hours per charge, but it also fast charges the iPhone when you just need the juice.
   
  There isn't anything on the market like it that I've seen. I'm also perplexed that more people aren't talking about it as it is the most intriguing transformer gear for the iPhone in the world and one I can't do with out - especially to hook up to my home system. I'm not a 24/96 person though I do have some albums. So, the loss of it isn't a problem for me. 
   
  Now, for the sound, it is similar to the older model: very clear highs, mid-focused with great separation in the bass. There is background noise if you use sensitive earphones, but it's regulated and not grainy. Again I'll say it, I will be picking one up at the headphone show... or borrow this one and leave somewhere... (evil grin).


----------



## AnakChan

Nice one. Which OpAmp are you reviewing? I've got the AD8397 (mine), & OPA1612 (loaner) which I wrote a review in the previous page. There's a newer AD8066 OpAmp coming up (or actually a guy in Oz has just bought one) which I'm hoping to get my hands on to test and review too.


----------



## shigzeo

I've got the OPA2134 in 'mine' which is according to Venture, a standard spec. It really sounds good. Have you tried all these with diff opamps, or are you changing them yourself? I've not opened up (and won't) the loaner as ... it is a loaner. When I get mine, I'll do it for sure.


----------



## AnakChan

I started with Muses8820 and soon after the BB OPA2134 in Sept/Oct. Then in Dec they announced they offered OP-275, AD8397, & OPA-2604 upgrades. I upgraded my Muses8820 to OP-275 (then sold it off to a friend), & the OPA2134 to AD8397 and I still have this. I never tried the OPA-2604 though.
   
  http://www.head-fi.org/t/533084/venturecraft-go-dap-gd-04-for-iphone-4/45#post_7995394
   
  Recently I was given the OPA1612 & Muses8820 ('cos I forgot what it sounded after so many months) to listen and I came up with the review I quoted in my previous post. I've returned the Muses8820 for now and hope to get the AD8066 next month to test that too.
   
  So far though, I have tested all but think I still like the AD8397 and the OPA1612 a very close second.
   
  When we meet at the May festival, I'm happy to bring along both OpAmps for you to have a listen - hope you have some closed IEMs or headphones .
   
  I don't know your opinion, but at least to me the Go-DAP triumphs over the CLAS (which I still own), and the HP-P1.


----------



## shigzeo

I will love to hear the AD8397 - that is a favourite of mine. I'll bring my Sleek Audio CT7 - nothing more closed exists in my lineup now, and my Audio Technica ES10 and maybe DT1350. No, that is too much. But I'll be getting one as the BB OPA 2134 is pleasant enough and the features for the price are killer. I'm getting a hardware converter this weekend to test how well the optical is implemented vs. MacBook Pro and Airport Express and Edirol FA-66. Oh yes, and against the CLAS Solo. 
   
  As a single unit, nothing exists to compare. Again, the original, non-digital version of the GoDap is a favourite of mine.


----------



## AnakChan

You should know though that optical out of the Go-DAP ain't it's best. Sounds rather flat compared to optical out of the Mac (or iBasso DX100).
   
  I've talked to VentureCraft about it and they think it's due to the upsampling from 44.1kHz -> 48kHz. However I've got some AAC at 48kHz and it sounds flat still. Something about the Go-DAP's optical out implementation that, at least to my ears, sound dull.


----------



## shigzeo

I've not tried it yet. That will be an important matter for me to suss as the coax of the CLAS is something I love.


----------



## shigzeo

I've not tested for jitter yet, but the actual output of the Unit 4.0 is fine. What system were you using to convert the signal to analogue? And when you compared it to other system, you used the same converting equipment? My system isn't that great now for converting to analogue, so I need some time on this. I'm awaiting one piece to allow me to test using my external card. Using my MacBook Pro's internal digital input is pretty poor.


----------



## AnakChan

My chain is Benchmark DAC1 Pre -> Stax SRM-727A -> SR-009.
   
  Various transports I've tried are :-
 Go-DAP via Optical
  Late '09 iMac 27" via Optical
  iBasso DX100 via Optical & Coax
  Apple TV V1
   
   
  I also tried a Lavry DA11 prior to purchasing the Benchmark DAC1 Pre. At first the Go-DAP sounded so dull I actually thought there was something wrong with it or the connection. Then trying various optical cables, I realised that this was the best the Go-DAP's optical could do (i.e. nothing wrong with the component chain).


----------



## shigzeo

Very interesting. Thank you.


----------



## Ehr33

AnakChan, I'm intend to combine it with my M80. Coming from HD650 & Triple.Fi 10, to me the M80 is less punch and lack of sparkle. Will this do the job? How is it with Triple.Fi 10?


----------



## AnakChan

Quote: 





ehr33 said:


> AnakChan, I'm intend to combine it with my M80. Coming from HD650 & Triple.Fi 10, to me the M80 is less punch and lack of sparkle. Will this do the job? How is it with Triple.Fi 10?


 

 You mean something like this?? :-

 http://www.head-fi.org/t/552014/pictures-of-your-portable-rig-part-xv/3225#post_8051991
   
  It's rather interesting that you find the M80 less punch. Do you mean bass? As for sparkle, do you mean treble? I personally do find the M80 to be a little treble veiled. But it depends on the genre of music. Overall though, I find that the combination works. The AKM DAC and the AD8397 OpAmp does extend the M80's treble somewhat (over straight out of the iPhone headphone jack).
   
  I must admit I cannot remember how the TripleFi 10's sound like as I sold them off back last November.


----------



## Ehr33

anakchan said:


> You mean something like this?? :-
> 
> http://www.head-fi.org/t/552014/pictures-of-your-portable-rig-part-xv/3225#post_8051991
> 
> ...




Yes! Thinking of the Burr Brown edition, because I'm familiar with the audio quality of OPA2134. But what I'm hoping for it be able to bump the mid bass and high of M80. Also by mean better DAC, means better audio quality for Triple.fi? How is it with IEM? Any channel imbalance? Noise?


----------



## brumma

Will 3rd party audio apps like Equalizer still work with the GO-DAP?  I know many here prefer not to EQ their music, but I need to in order to compensate for a partial hearing loss in one ear.  Besides, I like to be able to tweak the curves to compensate for the deficiencies of the headphones I am using.  Will the EQ still be processed, or is it bypassed by the GO-DAP?


----------



## AnakChan

Quote: 





ehr33 said:


> Yes! Thinking of the Burr Brown edition, because I'm familiar with the audio quality of OPA2134. But what I'm hoping for it be able to bump the mid bass and high of M80. Also by mean better DAC, means better audio quality for Triple.fi? How is it with IEM? Any channel imbalance? Noise?


 
   
  I have to admit I don't remember the Burr Brown OPA2134 since I owned it in that configuration for only a month last year then quickly upgraded to the AD8397 OpAmp. Depending on how much of a bump you're looking for, it wasn't enough for me. I agree with you that the treble in the M-80 is a little flat to a little veiled, at least compared to the other IEMs/headphones I've owned. The AKM DAC to me sounds more detailed and clean compared to the HP-P1. In fact (possibly I didn't have good amps for my CLAS?), I preferred the Go-DAP (with AD8397) over the CLAS+Pico Slim or CLAS+SR-71B.
   
  Note: My opinion of the Go-DAP may change depending on my recently acquired ALO Audio Rx Mk3.
   
  I also don't remember the Triple Fi's as I got rid of them last year but from what I do remember, the Go-DAP did reveal a little more of what the Triple Fi's are capable of. I've used the Go-DAP more with my Unique Melody Merlins more than with other IEMs. I didn't notice any channel imbalance in the 8 months of owning 2xGo-DAPs and 2 other loaners from VentureCraft. The same with noise - if anything good recording is probably important.
   
  I'm hoping to be able to get a 3rd loaner from VentureCraft, this time the Go-DAP 4.0 with the AD8066 OpAmp.
   
  Quote: 





brumma said:


> Will 3rd party audio apps like Equalizer still work with the GO-DAP?  I know many here prefer not to EQ their music, but I need to in order to compensate for a partial hearing loss in one ear.  Besides, I like to be able to tweak the curves to compensate for the deficiencies of the headphones I am using.  Will the EQ still be processed, or is it bypassed by the GO-DAP?


 
   
  To be honest I don't know about Equalizer. But I do know that FLACPlayer works fine through the Go-DAP, and default Apple player's preset equaliser works fine - i.e. not bypassed by the Go-DAP.


----------



## Ehr33

anakchan said:


> I have to admit I don't remember the Burr Brown OPA2134 since I owned it in that configuration for only a month last year then quickly upgraded to the AD8397 OpAmp. Depending on how much of a bump you're looking for, it wasn't enough for me. I agree with you that the treble in the M-80 is a little flat to a little veiled, at least compared to the other IEMs/headphones I've owned. The AKM DAC to me sounds more detailed and clean compared to the HP-P1. In fact (possibly I didn't have good amps for my CLAS?), I preferred the Go-DAP (with AD8397) over the CLAS+Pico Slim or CLAS+SR-71B.
> 
> Note: My opinion of the Go-DAP may change depending on my recently acquired ALO Audio Rx Mk3.
> 
> ...




Looks like the Triple.fi would benefit more from it than the M80. From my past experience AKM DAC (Behringer DEQ2496) + Burr Brown OPA2134 (DIY HP amp) did match well, rich mid with detailed highs, but that's with HD650. With the Merlins, what is your gain setting? At what position will be your volume knob?


----------



## AnakChan

Quote: 





ehr33 said:


> Looks like the Triple.fi would benefit more from it than the M80. From my past experience AKM DAC (Behringer DEQ2496) + Burr Brown OPA2134 (DIY HP amp) did match well, rich mid with detailed highs, but that's with HD650. With the Merlins, what is your gain setting? At what position will be your volume knob?


 
  You're right about the value of amps on the TripleFi vs M-80. IMHO (and I've written it before) that the M-80 is already quite well tuned and I find that it benefits little from DAC/Amps. That's not to say that there is no difference. There is, but it's minor in comparison to some other headphones.
   
  Admittedly on the Go-DAP i listen to it on High gain. But on the upgraded Go-DAP (with the RK73 upgrade), the low/high gain doesn't change that much. Whereas the stock Go-DAP 4.0 the low/high gain makes a bigger difference.

 I do listen to things rather loudly so around the 1:30 -> 2 o'clock range.


----------



## Ehr33

1 to 2 o clock onthe Merlins? What will it be on the M80 and your Ultrasone?


----------



## brumma

Quote: 





anakchan said:


> To be honest I don't know about Equalizer. But I do know that FLACPlayer works fine through the Go-DAP, and default Apple player's preset equaliser works fine - i.e. not bypassed by the Go-DAP.


 
   
  One can only assume that if the others work so will Equalizer.  Thanks!


----------



## AnakChan

Quote: 





ehr33 said:


> 1 to 2 o clock onthe Merlins? What will it be on the M80 and your Ultrasone?


 

 I can't remember what I listen to it on my M80. I just sold it off to my friend 'cos ever since I got my Merlins, I actually stopped taking the M80 out. On my Ultrasone Ed8's probably around the 2 o'clock (starts from around from 7 o'clock - I have to state this 'cos the Go-DAP doesn't have a marker on the knob).


----------



## DimitriTrush

to AnakCHAN. It was cool meeting you at the Headphone show. I got to try both VAMP and we have GoDAP here. It is really impressive and does so many things. I listen with VMODA M headphones and at the office with the Q701 headphones and with Fischer Audios FA011. It all sounded very good but not at so high volumes as you.


----------



## Ehr33

anakchan said:


> I can't remember what I listen to it on my M80. I just sold it off to my friend 'cos ever since I got my Merlins, I actually stopped taking the M80 out. On my Ultrasone Ed8's probably around the 2 o'clock (starts from around from 7 o'clock - I have to state this 'cos the Go-DAP doesn't have a marker on the knob).




Thanks for the info! That's really help alot!


----------



## brumma

I was searching around for any reviews of the Go-DAP 4.0 and stumbled across this:
   
http://www.youtube.com/watch?v=gVvmYK0XueM
   
  I am a little surprised by his conclusions since I've heard nothing but good feedback for the unit here at head-fi.  Of course, I have never heard of this guy either, so I have no idea if he is credible.  Would anyone care to comment?


----------



## AnakChan

brumma said:


> I was searching around for any reviews of the Go-DAP 4.0 and stumbled across this:
> 
> http://www.youtube.com/watch?v=gVvmYK0XueM
> 
> I am a little surprised by his conclusions since I've heard nothing but good feedback for the unit here at head-fi.  Of course, I have never heard of this guy either, so I have no idea if he is credible.  Would anyone care to comment?



I did . I commented back on Snazzy's YouTube a month back. I've had at least 4xGo-DAPs in my hands in the past 9 mths in various OpAmp combinations. I disagree with his opinion about the SQ & bass. But I do agree with him about the battery.


----------



## shigzeo

I really like the Go-DAP 4, but I feel, too, that the SPDIF output is done poorly. I get that Venturecraft have a certain sound to output, but it is quite different to the older Go-DAP, warmer and rolled off in the highs rather than the lows as the old one was. Anyway, I've written a comparison (heavily weighted I'll admit, but one I feel is 'fair' considering both the CLAS and Unit 4.0 claim SPDIF output) at TouchMyapps. There is nothing like the Unit 4.0 apart from the older Go-DAP. To be honest, from the headphone amp output, I prefer the older unit though the newer one with OPA2134 is nice.


----------



## gkanai

Shigzeo, thanks for the writeup.

I've decided against the Unit 4.0 because of future-compatibility concerns.

I've decided against the CLAS because of size (I don't want to carry both a CLAS and amp.)

So I'm waiting for the Go-Dap X unit and will try that against the HP-P1 and will make my decision then.


----------



## shigzeo

The GoDAP X seems interesting as it works from computer and from iDevice. Will have compromises to be sure, but comes at a great price.


----------



## brumma

Quote: 





anakchan said:


> I did
> 
> 
> 
> ...


 
   
  I didn't read through all of the posts on his YouTube page, but I will now.  Is that where you commented?
   
  Quote: 





gkanai said:


> I've decided against the Unit 4.0 because of future-compatibility concerns.


 
   
  Why not just keep your iPhone 4 after you upgrade to the iPhone 5 and use it as a dedicated DAP?  That's what I plan to do.  It would mean more free space for music too.


----------



## brumma

AnakChan & shigzeo, do you guys think that the audio quality is enough of an improvement over the built-in headphone out of the iPhone 4 to warrant a purchase for use as an amp only?  In other words, is it worth it if I never plan to use the optical out?  My headphones and IEMs are pretty easy to drive, and I only rarely plug my iPhone into the stereo.


----------



## AnakChan

Quote: 





brumma said:


> AnakChan & shigzeo, do you guys think that the audio quality is enough of an improvement over the built-in headphone out of the iPhone 4 to warrant a purchase for use as an amp only?  In other words, is it worth it if I never plan to use the optical out?  My headphones and IEMs are pretty easy to drive, and I only rarely plug my iPhone into the stereo.


 
   
  Just a point of clarification, the optical out is when you want to use the iPhone purely as a transport to an external DAC/Amp. The other use is to use the Go-DAP as a DAC+Amp-combined. In other words you cannot use the Go-DAP as an Amp-only, or as a DAC-only.
   
  So if you don't care about the optical out (e.g. like me, I never use the Optical out for listening, more for testing which it's clearly isn't its forte), then using the Go-DAP as a DAC+Amp is to me a clear improvement over straight out of the iPhone 4/S.


----------



## DimitriTrush

Shigzeo borrowed my unit. It is plenty power for headphones more than the regular iPhone. He says for IEM earphones it isnt as good as iPhone is normal but I disagree. The sound is so much rich and smoother and beautiful than the regular iPhone. Maybe you like smooth warm sound which shigzeo doesnt care about for but if your like me and love that sound then you love this I guarantee it. Shigzeo cares about audiophile benchmark and all this signal stuffs and I care all about the sound and that it.


----------



## brumma

Thank, gents.  That clarifies things a bit for me.  
   
  AnakChan, I've read your write-ups on your upgraded units, but couldn't find any info from you on the OPA2134.  Did you post anything and, if so, can you point me in the right direction?  I have to admit that I am still confused by all of the different amp upgrade options and the sound qualities of each.  Would you recommend getting the DAC & Gain upgrades with the standard OPA2134, or are they only meant to be coupled with the upgraded amps?


----------



## AnakChan

Quote: 





brumma said:


> Thank, gents.  That clarifies things a bit for me.
> 
> AnakChan, I've read your write-ups on your upgraded units, but couldn't find any info from you on the OPA2134.  Did you post anything and, if so, can you point me in the right direction?  I have to admit that I am still confused by all of the different amp upgrade options and the sound qualities of each.  Would you recommend getting the DAC & Gain upgrades with the standard OPA2134, or are they only meant to be coupled with the upgraded amps?


 
  Unfortunately I didn't upgrade in stages, I did everything in one hit - the DAC/Gain, and the Op Amp. I think the sound differences I hear are primarily on the OpAmp upgrade but whether the other component upgrades help to make the OpAmp differences more obvious, I'm not certain. When I was talking to VentureCraft, they were talking about those upgrades "opening up" the OpAmp more (I have to be honest I don't really know what that means).
   
  If I had to do it all over again and if had to choose only 1 component to upgrade, I'd probably pick the OpAmp, but ideally do all 3.
   
  I didn't write much about the OPA2134 as I had it only for a brief period of time (Oct -> Nov '11), but had the AD8397 for a much longer period. I've tried the OPA1612 for just over 6 weeks now. takoyaki wrote briefly about the OPA2134 :-

 http://www.head-fi.org/t/533084/venturecraft-go-dap-gd-04-for-iphone-4/45#post_7872045


----------



## brumma

What makes the choice of another opamp an "upgrade"?  Are the other opamps generally regarded as being better quality / sound, or is it really just a matter of taste?  I am a newbie, wannabe audiophile, and am still trying to sort through all of the terminology so I am going to ask for a bit of advice...
   
  I mostly listen to rock in it's various forms, as well as a bit of jazz.  My headphones are Audio Technica ATH-ESW9, Bowers & Wilkins P5, and Audéo PFE-112.  I also own a pair of ATH-M50s, but am looking to sell them.  I am rather sensitive to sibilance, but don't like too much treble roll-off.  I'm not sure how to express my midrange preferences.  My only reference is what I've heard of "scooped" sounding headphones / EQ--I'm not a fan, so maybe you can draw conclusions from that.  I prefer bass to be tight and punchy, without any mid-bass bloom.  Do any one of these particular opamps work better than the others for this combination of tastes?


----------



## AnakChan

From VentureCraft themselves since the Go-DAPs are mostly sold as their base models OPA2134 & Muses 8820E. If you want to have the AD8397, OP-275, or OPA-2604, you'll have to send back your Go-DAP OPA2134/8820E back to them (and pay a fee) for that OpAmp upgrade. There were some limited Go-DAPs that were sold on the shelf with those OpAmps, but I believe the retail stores requested VentureCraft to make those specially for them - as such limited.
   
  The term "Upgrade" from an SQ perspective, IMHO, could still apply going from OPA2134/8820E to the AD8397/OPA1612 'cos of the improvement to the extensions in bass/treble, & the improvement in clarity/detail. As one may say if they could "upgrade" the sound of the iPhone by adding an external DAC/Amp.
   
  I think if you're sensitive to sibilance, I think it's better controlled by the choice of headphones rather than by the OpAmps. At least in the Go-DAP implementation of various OpAmps, the changes are slight in comparison to the headphones. I'm not familiar with most of the headphones you have but have heard the B&W P5 (which to me are dark for my tastes). Whether you're opting the base Go-DAP 8820E vs say the AD8397 or OPA1612, the treble extensions of the latter OpAmp isn't going to make the B&W P5 dramatically sibilant. You'll hear the differences but more subtly.


----------



## brumma

Quote: 





anakchan said:


> From VentureCraft themselves since the Go-DAPs are mostly sold as their base models OPA2134 & Muses 8820E. If you want to have the AD8397, OP-275, or OPA-2604, you'll have to send back your Go-DAP OPA2134/8820E back to them (and pay a fee) for that OpAmp upgrade. There were some limited Go-DAPs that were sold on the shelf with those OpAmps, but I believe the retail stores requested VentureCraft to make those specially for them - as such limited.
> 
> The term "Upgrade" from an SQ perspective, IMHO, could still apply going from OPA2134/8820E to the AD8397/OPA1612 'cos of the improvement to the extensions in bass/treble, & the improvement in clarity/detail. As one may say if they could "upgrade" the sound of the iPhone by adding an external DAC/Amp.
> 
> I think if you're sensitive to sibilance, I think it's better controlled by the choice of headphones rather than by the OpAmps. At least in the Go-DAP implementation of various OpAmps, the changes are slight in comparison to the headphones. I'm not familiar with most of the headphones you have but have heard the B&W P5 (which to me are dark for my tastes). Whether you're opting the base Go-DAP 8820E vs say the AD8397 or OPA1612, the treble extensions of the latter OpAmp isn't going to make the B&W P5 dramatically sibilant. You'll hear the differences but more subtly.


 
   
  As a first-time buyer, I assume I can order a new unit that already has the upgrades installed for the additional cost, correct?  I believe you mentioned that the AD8397 was your favorite opamp--what makes you prefer it over the others?  Is it the extension to the bass/treble you mentioned?  Just to clarify, what is meant by the term "extension"?  Do you mean that there is less roll-off and it is actually hitting higher and lower frequencies?  Sorry for so many questions.


----------



## AnakChan

Quote: 





brumma said:


> As a first-time buyer, I assume I can order a new unit that already has the upgrades installed for the additional cost, correct?  I believe you mentioned that the AD8397 was your favorite opamp--what makes you prefer it over the others?  Is it the extension to the bass/treble you mentioned?  Just to clarify, what is meant by the term "extension"?  Do you mean that there is less roll-off and it is actually hitting higher and lower frequencies?  Sorry for so many questions.


 

 So if you want to have anything other than the Burr Brown OPA2134 (http://venturecraft.jp/gadget_en/gd04_buy.php), then you'll need to mail VentureCraft for a customised order. They will then tell you the price of the customised Go-DAP 4.0.
   
   
   
  Have a read on post #55 about my comments for my preference of the AD8397. My definition of extension is that I can hear the highs and lows more easily. Whether that means in the frequency chart if the dB's are higher at those frequencies, I'm not entirely certain - but I think that to be the case.


----------



## shigzeo

This is a late reply, I'm sorry.
   
  As to quality, I think you have qualify what quality means. If it means being closest to the actual waveform and reference level, then no, the GoDAP isn't even close. But, it adds more power and has a pleasant roll off like a NOS DAC that makes certain sharp headphones/speakers sound more mellow, laid back. As a reference, it really does fall flat, but I can't imagine that is what Venturecraft were going for. This DAC/amp is pleasant, not perfect.
   
  I'm sorry I'm late with this.
   
  The iPhone has a pretty damn good output system, but it is reference aimed, meaning it will be sharp and as flat as possible. If you have a newer iPhone, like iPhone 4S, you will find that it has enough headroom to drive low Ω balance armature phones perfectly. But, it will retain that pristine reference sound. The GoDAP honestly doesn't retain resolution as well as the iPhone does, but it is warmer. Some might call it more involved.
   
  It has a quality all its own, but it isn't the quality defined as 'better'.
  Quote: 





brumma said:


> AnakChan & shigzeo, do you guys think that the audio quality is enough of an improvement over the built-in headphone out of the iPhone 4 to warrant a purchase for use as an amp only?  In other words, is it worth it if I never plan to use the optical out?  My headphones and IEMs are pretty easy to drive, and I only rarely plug my iPhone into the stereo.


----------



## brumma

Quote: 





anakchan said:


> I think if you're sensitive to sibilance, I think it's better controlled by the choice of headphones rather than by the OpAmps. At least in the Go-DAP implementation of various OpAmps, the changes are slight in comparison to the headphones. I'm not familiar with most of the headphones you have but have heard the B&W P5 (which to me are dark for my tastes). Whether you're opting the base Go-DAP 8820E vs say the AD8397 or OPA1612, the treble extensions of the latter OpAmp isn't going to make the B&W P5 dramatically sibilant. You'll hear the differences but more subtly.


 
   
  I agree that the choice of headphones is more of a variable, and I also consider the B&W too dark.  I really need to boost up the treble and deep bass quite a bit, while lowering the mid base. The base still sounds a bit too loose on the P5 for my taste.  The Audio Technicas do a much better job of controlling the bass.  I keep the mid-range relatively flat for both the P5 and ESW9.  That being said, any additional advice on which opamp to order?  I wonder if I should just go with the base OPA2134 version (since I am really new to this), and figure out what I like as I go along.  If I am unsatisfied, then I can always upgrade later.  Besides, $365 is a lot easier to swallow right now than $600-ish.  (Gotta pay the bills, and the car is due for a service.)
   
  I just noticed that my location is not listed on my profile--I am located in the States.  Is it even possible to order the upgrades and have them delivered here?


----------



## AnakChan

The upgrades are possible later on. As you probably read in my posts back in Jan, I upgraded both my Muses 8820E & Burr Brown OPA2134 to the OP-275 & AD8397.

Your problem will be when you want to upgrade later you'll have to ship it back to Japan for it to be done. But, naturally it is possible.


----------



## brumma

Quote: 





anakchan said:


> The upgrades are possible later on. As you probably read in my posts back in Jan, I upgraded both my Muses 8820E & Burr Brown OPA2134 to the OP-275 & AD8397.
> Your problem will be when you want to upgrade later you'll have to ship it back to Japan for it to be done. But, naturally it is possible.


 
   
  Yes, I did read that.  What sparked your interest in pursuing the upgrades?  Were you unsatisfied with the sound of the original, or was it just curiosity to try something different?
   
  Shipping it back to Japan isn't really a problem.  I'm more worried about ordering something I may not like because I don't have a clue about what I'm doing.


----------



## AnakChan

brumma said:


> Quote:
> 
> 
> 
> ...



Curiosity did it for me. I was basically learning about OpAmps then (am still now)...

e.g. Something I learnt from the folks on the industry, most makers actually scratch off the surface of the OpAmps so that when you open it up, you actually have no idea what you're getting (nor how expensive or cheap it is).


----------



## Currawong

Regarding OPAMP price, off the top of my head, pretty much the only expensive common ones are the OPA627, OPA2134 and LT1364.  The newer 49710 (single) and 49720 dual are supposed to be essentially the same as the 1364, but are much cheaper. I haven't checked lately what the newer ones cost, but straight from the manufacturer or one of the big electronic parts distributors almost all OPAMPs cost very little. It's also trivially easy to figure out what OPAMP is being used even if the markings have been removed.


----------



## Javierelizondo

Quote: 





brumma said:


> I was searching around for any reviews of the Go-DAP 4.0 and stumbled across this:
> 
> http://www.youtube.com/watch?v=gVvmYK0XueM
> 
> I am a little surprised by his conclusions since I've heard nothing but good feedback for the unit here at head-fi.  Of course, I have never heard of this guy either, so I have no idea if he is credible.  Would anyone care to comment?


 
  I own the GoDap 4.0.   It works great.   I have it running a Sennheiser HD-800, which are very difficult to drive, and it does the job with them very good.   I do not agree with the reviewer that the sound is not good because of thin bass.   It's a pitty that a review like this could prevent you to experience a good amplifier for the size.    I have had no problem with the battery because I almost never use the setting in which the amp battery recharges the iPhone battery.    I only use this setting when my iPhone has less than 10% charge, and its not often.   Read reviews somewhere else.


----------



## 9VARZ

Kinda TL;DR since I'm late to join the iPhone 4S party....apologies!  
	

	
	
		
		

		
		
	


	



   
  Anyway, with the discontinuation of the Alesis AmpCase, am I right to say that the Go-DAP is pretty much the only reasonably portable option left on the market? If so, what is the ultimate/recommended configuration to go for in terms of speccing it? Trying to look for a balanced, neutral sound here.
   
  Also, anyone care to explain how would one handle the issue of answering phone calls on the Go-DAP 4?
   
  (I know the sound on the Fostex and the CLAS stack would be brilliant, but there is absolutely no way I can afford losing my phone and/or audio stack every week. Phone crime here is still way too high.)
   
  If there are other high-end options, would anyone be so kind as to list them out? We'll cap the budget at the HP-P1's level for now and I intend to use only IEMs with them (probably mic-ed). Cheers!


----------



## AnakChan

Quote: 





9varz said:


> Kinda TL;DR since I'm late to join the iPhone 4S party....apologies!
> 
> 
> 
> ...


 
   
  When you say "reasonable portable option left", I guess you mean integrated? If so then yes. There are other portable solutions too with some high quality SQ however there'll be some compromises in other forms. e.g. quite recently the iBasso DX100 has been quite a hit (not exactly at HP-P1 prices though) and it's SQ is superb, however its UI is slow and clunky (so you can't treat it like a jukebox with all your songs as it takes a long time to index them -everytime- you powercycle or update the microSD card). And you'll be carrying two devices - the DX100 DAP & your phone.
   
  The Sony NW-Z series is also quite a nice sounding DAP but it's memory capped with no room for expansion (same as the iPhone too I guess). Again carrying two devices, your phone and the DAP (but slimmer and cheaper than the DX100 at least).
   
  And you've already ruled out multi-component stacks for aforementioned reasons.
   
  So the Go-DAP 4.0 is probably the most integrated nice sounding SQ unit I personally can think of for now in the market. My personal preference of the OpAmp is the AD8397 but I don't know if VentureCraft has anymore of those. There other popular one is the OPA1612, and more recently VentureCraft has added AD8066 to their OpAmp option suite (but I've not listened to them yet).


----------



## 9VARZ

Interesting stuff, AnakChan! Arigatou!
   
  Yes, I'm trying to look for something as integrated as possible.
   
  I've had the iPhone 2 with the FiiO E7 and my experience with that setup was so bad, I simply removed the E7 from the equation within 2 weeks of (mis)use. I was missing too many incoming calls, the audio wasn't *that* fantastic compared to the TRRS output (since I still didn't bypass the iPhone's DAC), yada-yada.
   
  Unfortunately, I don't think I'll be looking for a DAP because I technically could get myself an iPod Classic, "stack" it with a HP-P1 and still use it reasonably discreetly. Also, using a DAP would effectively render my iPhone into another touch-UI brick that I'd loved to hate (since I'm the sort that don't put more than a handful of apps on the phone). Also, I have a niggling suspicion that I would end up missing even more critical calls and texts yet again if I venture down that path. 
   
  I've just came across the V-Moda VAMP which looks like a re-badged Go-DAP. I wonder if I should bother with that too... Hmmm.....


----------



## AnakChan

The VAmp is a customised Go-DAP - with the OPA1612 OpAmp & 2200mAh battery. It also has further it's own "custom tuning" with the VTune as opposed to Go-DAP's ASR (Acoustic Sound Retriever).


----------



## 9VARZ

Noted.
   
  So effectively, I'm back to square one in terms of options.  (；¬д¬)
   
  Come to think of it, the DX100 may not be a bad option if it weren't for the fact that it's sold out. 
   
  Decisions, decisions.......
   
  And rumours of the impending iPhone 5 really isn't helping matters a bit! XD


----------



## brumma

Quote: 





anakchan said:


> The VAmp is a customised Go-DAP - with the OPA1612 OpAmp & 2200mAh battery. It also has further it's own "custom tuning" with the VTune as opposed to Go-DAP's ASR (Acoustic Sound Retriever).


 
   
  Any word on price?  I'm waiting for info so I can decide between the Vamp and the Go-DAP.  Do you have any other details?


----------



## shigzeo

Venturecraft have tailored the sound of the GoDap to be warm and very smooth with a tightening of the upper bass. It is taught and very nice to listen to, but it isn't a reference flat sound. I haven't heard the iBasso, but have the C4, the Hifiman options, etc. In some ways, the GoDap is a slightly more taut, well defined Hifiman sound, but with more background noise. If you like the gradual roll off in the high frequencies of the Hifiman, then the GoDap is excellent.
   
  Couple that with gapless playback, playback of all industry standards and of FLAC with apps like Equaliser Pro, and you have in one unit the most complete portable music listening environment you can get your hands on. The Dx100 won't playback music as well as the iPhone/GoDap no matter the hardware. It may have higher fidelity internal components though, but that is a bag of bones without the software to deliver flawless playback through a transport.


----------



## brumma

I don't see that this has been covered anywhere, but I may have overlooked it... Do any of the built-in headphone cable remotes work with the Go-DAP's headphone out? I assume volume control wouldn't, but what play controls? Just curious.


----------



## AnakChan

No it doesn't. Nor would remotes work with Fostex HP-P1, or CLAS+Amp combo's too.


----------



## brumma

Quote: 





anakchan said:


> My personal preference of the OpAmp is the AD8397 but I don't know if VentureCraft has anymore of those. There other popular one is the OPA1612, and more recently VentureCraft has added AD8066 to their OpAmp option suite (but I've not listened to them yet).


 
   
  FYI, I contacted Venturecraft about getting a custom Go-DAP, and the OPA1612 and AD8397 are no longer available.


----------



## brumma

Quote: 





anakchan said:


> No it doesn't. Nor would remotes work with Fostex HP-P1, or CLAS+Amp combo's too.


 
   
  Thanks for the clarification.


----------



## AnakChan

brumma said:


> Quote: Originally Posted by AnakChan My personal preference of the OpAmp is the AD8397 but I don't know if VentureCraft has anymore of those. There other popular one is the OPA1612, and more recently VentureCraft has added AD8066 to their OpAmp option suite (but I've not listened to them yet). FYI, I contacted Venturecraft about getting a custom Go-DAP, and the OPA1612 and AD8397 are no longer available.



Yeah, it seems when VentureCraft comes up with some OpAmp versions, they order and make only a limited number. AD8397 is also unavailable now (& I don't think they have plans to bring in anymore).

The OPA1612 maybe unavailable now but I wonder what will happen when V-Moda wants more VAmps (which are OPA1612 based). I'm sure VentureCraft can't just simply switch on them so quickly the way they do with the Go-DAPs.

Mind you, I'm literally, right now, reviewing the AD8066 VentureCraft has loaned me (they want me to write a mini-impression), and for the 1st hr, I wasn't impressed with them vs. the OPA1612. But after the quick 1 hr burn-in, the tables have turned!! The AD8066 is sounding more 3 dimensional than the OPA1612!! I'm gonna burn them in longer to compare against my personal fav AD8397.

If the AD8066 continues to sweeten over a longer burn-in, I think V-Moda may have jumped the gun with the OPA1612 for the VAmp.

Edit: the differences aren't night 'n day but more apparent on some tracks than others.


----------



## brumma

Quote: 





anakchan said:


> Yeah, it seems when VentureCraft comes up with some OpAmp versions, they order and make only a limited number. AD8397 is also unavailable now (& I don't think they have plans to bring in anymore).
> The OPA1612 maybe unavailable now but I wonder what will happen when V-Moda wants more VAmps (which are OPA1612 based). I'm sure VentureCraft can't just simply switch on them so quickly the way they do with the Go-DAPs.
> Mind you, I'm literally, right now, reviewing the AD8066 VentureCraft has loaned me (they want me to write a mini-impression), and for the 1st hr, I wasn't impressed with them vs. the OPA1612. But after the quick 1 hr burn-in, the tables have turned!! The AD8066 is sounding more 3 dimensional than the OPA1612!! I'm gonna burn them in longer to compare against my personal fav AD8397.
> If the AD8066 continues to sweeten over a longer burn-in, I think V-Moda may have jumped the gun with the OPA1612 for the VAmp.
> Edit: the differences aren't night 'n day but more apparent on some tracks than others.


 
   
  So the OPA1612 and AD8066 have similar sound coloring?  How does the AD8066 compare to your favorite AD8397?  I read one criticism of the AD8066 that said it had a "boring mid-range."  Any thoughts on why they may have said that, sincet seems as though you are enjoying your sample?  Getting ready to pull the trigger myself.  Almost there...


----------



## AnakChan

I won't use the word coloring but I'd say similar signatures instead. Do bear in mind though with all the OpAmps I've tried with the GoDAP, the amps aren't vastly different (except for the Muses 8820E, OPA2134' & OP-275 maybe; but the OPA1612 & AD8066 are very similar with subtle differences, I'd personally put the AD8397 in its own category to what I'm listening -right now-).

So to answer your question about the AD8066 & AD8397, I'm not gonna mince my words today & say that the AD8397 still smacks the AD8066 in the face. The detail, depth and 3D-ness of the AD8397 still reigns. At some point though (depending on headphone synergy) the AD8397 could sound a little sibilant but that depends on the headphones & only some tracks.

I'm going to listen across more genre to give a more in-depth impression but for now I'd still prefer the AD8397, then a couple of steps away the AD8066 with the OPA1612 one step behind the AD8066.

Edit: Throwing in pix of my test today (AD8066, AD8397, iPhone4 S, new iPad, some el-cheapo iPod cable extender, UM Merlins)


----------



## AnakChan

So almost a month later I'm in a position to provide a more thorough review of the Go-DAP 4.0 with the AD8066 OpAmp. This has been a somewhat difficult listening experience because I've gone back and forth between the AD8066 & the OPA1612 on numerous occasions - each time burning in the AD8066 more (whilst the OPA1612 has had hundreds of hours of burn-in).
   
   
  What's the verdict? Believe it or not, I have found that the AD8066 and the OPA1612 so close to each other that they're almost indistinguishable from each other. In fact this is the reason why I had to go back and forth so many times 'cos each time I focused on each one, I found them so close that I didn't believe it myself and had to find difference between the two. And that's where it gets dangerous 'cos placebo starts to manifest (as such my June 12th comments to Brumma). So the final bottom line after many many hours of burn in of the AD8066, and many many hours of listening between the two (even giving myself a week's break in-between hrs of listening), my personal conclusion is that they are too similar to try to nitpick.
   
  But did I hear a difference between the two? I'd rather err on the side of caution to say that _*I'd like to think I did*_ for certain tracks only. I even whipped out my favourite AD8397 to confirm that my ears were tired from A/B-ing too long. As such the following are the rough notes I made during the comparison between the AD8066 and OPA1612, and later with the AD8397.
   
  According to Go-DAP 4.0 manufacturer, the AD8066's main feature is that it's a "FastFET" with a 145MHz which is supposedly suitable for "fast" music. As opposed to the other OpAmps VentureCraft has put into the Go-DAP, the OPA1612 is a "WideBandwidth" 40MHz, and the AD8397 being a 69MHz. For reference, the Muses 8820E is an 11MHz whilst the OPA2134 is 8MHz.
   
  I have to admit that OpAmp frequencies in this respect is beyond my knowledge. Although I understand these frequencies in computing terms but what it means to music (or as the manufacturer is alluding to, genre of music) I'm not certain. According to the makers, the reason why I may not hear a difference between the OPA1612 and AD8066 is that the music I listen to are may not see the benefit of the speed of the AD8066 - a reasoning I'm willing to accept.
   
   
 *Reboot: Back to Scratch Review*   
  As such, back to the roots of merely comparing the Go-DAP 4.0 with AD8066 against a barebones iPhone 4(S). What does an iPhone 4(S) user gain by using the VentureCraft Go-DAP 4.0 with an AD8066?
   
  The Go-DAP provides an integrated iPhone 4(S) jacket that's free of any external LOD cables and presents a multi-purpose/multi-component into a single integrated device.
   

   
  Size comparison to another popular multi-component setup with external LODs ands interconnects :-
   

   
  However, this doesn't mean that the VentureCraft Go-DAP 4.0 becomes obsolete with the iPhone 4(S). It basically works with any current iOS device with an iPod extended cable (NB: iPhone, iPod Touch, Nano, iPad. However it is not compatible to the iPod Classic). So in "worst case" scenario, it can operate in multi-component mode, like it's competitors.
   

   
*Features*
   

 AKM AK4353 DAC
 Analog Devices AD8066 OpAmp (Base OpAmps start from Muses 8820E or Burr Brown OPA2134)
 1580mAh battery that can be used entirely for the Go-DAP DAC/Amp, and/or charging your iPhone
 Low/High Gain Switch
 Acoustic Sound Retriever (ASR) to recover details lost in lossy compression
 Transport functionality by having 3.5mm Optical Out to an external DAC
 Manufacturer-upgradeable battery to 2200mAh
 Manufacturer-upgradeable OpAmp of customer's preference (menu-style offering from manufacturer)
   
*Practical Operation*
   
   
  The Go-DAP takes approx 4-5 hrs to charge the 1580mAh battery and when used completely in DAC/Amp (marked as "Amp" on the toggle switch) lasts approximately 7 hours of continuous use. When the battery is used to charge the iPhone instead (marked as "Amp-i" on the toggle switch), it lasts for approximately 1 hr and the iPhone is charged up to 48% (from a completely depleted absolute 0% battery charge). I usually use it in "Amp" mode unless I'm really running low on juice on my iPhone.
   
  The Go-DAP must be charged separately from use - i.e. you cannot simultaneously charge whilst actually using it. It charges via mini-USB at the base and has to be switched into Amp or Amp-i mode to charge. When the mini-USB is plugged in, and it's in either of those modes, it'll prioritise to charging instead of audio/listening mode.
   
  However if the mini-USB is plugged whilst the toggle switch is in "Sync/Off" mode, the Go-DAP is switched off and the mni-USB changes to pass-through mode and your iPhone will sync with iTunes. Naturally if there's no iPhone there, it doesn't do anything (including _NOT_ charging the Go-DAP!).
   
  Confused? Here's a table :-
   

   *Sync/Off* *Amp-i* *Amp* *Mini-USB In* iPhone/iTunes Sync Go-DAP Charging Only Go-DAP Charging Only *Mini-USB Out* Go-DAP 4.0 OFF Mode iPhone Charging/Music Mode Music Mode
  Go-DAP 4.0 Operational Chart     
  Meanwhile, the optical out is always on. It's the same jack port as the for the Single Ended 3.5mm headphone out.
   
  The 70mW+70mW (32 ohm) output drives most earphones and headphones well. Of course though if you have the "hard-to-drive" headphones like HD800s, Hifiman series, or LCD-2/3s then it would be somewhat of a struggle for the Go-DAP. V-Moda VAmp followers may note though that the VAmp version of the Go-DAP outputs 150mW+150mW. This feature, the ASR replaced with VQ, and the OPA1612 OpAmp are customisations specifically designed by the VentureCraft fo V-Moda.
   
*Sound Quality*
   
  The VentureCraft Go-DAP 4.0 in this AD8066 OpAmp iteration provides transparent and detail presentation over the straight headphone out of the iPhone 4S. Pretty much across all genre of music I've listened to - Classical, old 50s/60s West Coast Jazz, BossaNova, Vocal Jazz, 80s, 90's pop, and instrumental movie soundtracks some modern Hip-Hop - the tracks are presented in a more transparent way like a veil was lifted. There's more clarity across the frequency (although more prevalent in the mids and highs in most tracks, and some kinds of music, in the basses too). Basses in most songs are decently extended yet tightly controlled (e.g. picking Black Eyed Peas, Boom Boom Pow as an example). Bear in mind though the IEMs (Unique Melody Merlins, FitEar TO GO! 334) and headphones (Fostex TH900) I use with the Go-DAP are decent themselves.
   
  Vocals are also smoothly with clarity and precisely as opposed straight out of the iPhone, can sound somewhat muddy. The presentation of the mids also sound somewhat more 3 dimensional with a little more depth to the stage, whilst the overall soundstage is decently extended.
   
  Treble is also nicely extended. And although initially may sound a little harsh and sibilant, after a about a decent 1 week (off/on) burn in, the trebles are much smoother and controlled. The soundstage width and depth also extended nicely.
   
  In my honest opinion, although VentureCraft provides a suite of OpAmp options to the customer, the AKM AK4353 DAC plays a major part in it's ability to retrive sound quality and the OpAmp of choice further enhances what comes out of that DAC.
   
*Summary*
   
  Although I personally own a suite of other DAPs and DAC/Amp combinations and some can be challenging to the Go-DAP SQ-wise, none have so far been able to beat the integration of the Go-DAP into a neat little package with top quality sound. To strive for greater detail or greater amp power, a listener would have to sacrifice something else - primarily integration but to a lesser extent on-the-move portability. Of course one could carry a dedicated DAP but then would have to manage 2 devices - DAP and phone. For those who are happy to have their music on their iPhone and strive for improved sound quality without sacrificing integration, the Go-DAP is a neat package.


----------



## mokobigbro

My impression of using Go-DAP 4.0:
   
  I receive this about a month ago. 
   
  Packaging:
  I am very impressed with the packaging of Venturecraft Go-DAP 4.0. The unit when you receive is shrinkwrapped and 'floating' inside the box. You can bounce the box, drop it from 4-5 meters and the product would be safe. 
  The manual is also nicely done. It communicates confidence and thoughtfulness from the company. 
  (I am a distributor for high end recording equipment, and you'd be surprised units 10x the price of Go-DAP doesn't have a manual or as well written as this)
   
  The build quality is excellent too! Love the fact that it is Made in Japan, at a very modest price of $425. 
   
  Let's go straight to the sound:
   
  I use my Unique Melody Mage and my Mrspeakers Mad Dog to evaluate the Go-DAP. I didn't have any other portable dac/headphone amp to compare it with.
   
  UM Mage has a very balanced bass to mids frequency response. It sometimes lack high frequency extension. The reverb decay and details are often missing when listening straight from the iphone4s. 
  With Go-DAP, the difference are not subtle. It opens up the high frequency, and also added a bit of punch to the snare and guitar strumming. Vocal remains solid and the center of attention. Low end is tighter/cleaner as well. 
  Mrspeakers Mad Dog is a bit hard to drive. With my iphone4s volume all the way up, I still don't feel that it's giving enough volume. I had a different experience listening to the Mad Dog from a Dangerous Monitor ST headphone out. 
  With Go-DAP, the difference between iphone4S, it has cleaner bottom, tighter image and more extended high frequency. After listening to different reference songs, songs that I work on, I find that I am now confident to share the tone characteristics of Go-DAP.
   
  Go-DAP 
  Bass: It's got a clean, tight bass sound. Don't expect the unit to add more bass, but expect a cleaner bass.
  Mids: Somehow I felt that mids are tighter with Go-DAP than with the iphone4S. 
  Treble: It has a sparkly high frequency extension that is going to sound great with music that are sparse and 'reverby'. 
  Imaging: Imaging is tight. I can definitely tell clearly where the instruments and vocal sit with Go-DAP than without. Stereo field of instruments, types of delay/reverb chosen, processing on vocals are easily guessed. 
  Depth: Enough depth information and positioning of front to back of music/vocals. 
   
  With my UM Mage, I feel that Go-DAP has given an added value to the IEM. 
  With Mrspeakers Mad Dog however, I feel that Go-DAP is not really suitable for headphones that are hard to drive. Even at a higher gain, I still have to crank the gain till it's maxed out and still it couldn't drive the headphone easily. 
   
  As for things that can be improved:
   
  1. I wish I can still use the unit when the unit is still being charged.
  2. A switch for an inefficient headphone would be great
  3. A stronger battery  (have to switch back to my iphone4s)
  4. When the signal of phone was bad, even in the US, I experienced a dropout of sound and also signal interference.


----------



## WNBC

I picked up a used Go-DAPs for a good price and wanted to potentially mod it.  If I'm not worried about warranty can I go in an change the Op Amp?  OPA2134 is not wowing me, especially at the low end.  From what I am reading it sounds like everybody is ordering them custom from the factory but it appears I can get in the case with a hex wrench.  And the battery has ~500 charge/discharge lifetime which is longer than most would probably keep it anyway.  However, wouldn't hurt to pick up an extra battery for the future.  The previous owner probably did not put in many hours on it so I'm going to run it before I decide whether or not to keep it.


----------



## AnakChan

Not that I'd advocate modding the Go-DAP but if you're comfortable soldering SMD's, why not? Check out compatible pinout OpAmps though.

Outta curiosity where did the 500 charge limit come from?


----------



## WNBC

Instruction manual that came with the Go-Dap indicates 500 cycles.  
   
  Quote: 





anakchan said:


> Not that I'd advocate modding the Go-DAP but if you're comfortable soldering SMD's, why not? Check out compatible pinout OpAmps though.
> Outta curiosity where did the 500 charge limit come from?


----------



## StereoHeadphone

I just upgraded my iPhone 4 to iOS6 and it is causing major issues with the Go-Dap. It will still charge the iPhone even if it is in amp only mode. Is anyone facing similar issues?


----------



## DimitriTrush

Quote: 





stereoheadphone said:


> I just upgraded my iPhone 4 to iOS6 and it is causing major issues with the Go-Dap. It will still charge the iPhone even if it is in amp only mode. Is anyone facing similar issues?


 

   I suggest you to contact the manufacturer to see if there is a remedy to solve  your GODAP 4 issue.


----------



## AnakChan

I've just informed VentureCraft of your issue.


----------



## AnakChan

So VentureCraft just tweeted that they're checking the iOS6 & Go-DAP 4.0 always charging regardless of Amp or i-Amp mode. They will announce their findings later this week. Presumably this is also applicable to V-Moda VAmp too then.


----------



## StereoHeadphone

Thanks AnakChan, hopefully this issue can be resolved easily.


----------



## brumma

Same problem here with the V-MODA VAmp.


----------



## AnakChan

Quote: 





brumma said:


> Same problem here with the V-MODA VAmp.


 
   
  Talk to V-Moda customer service. I believe they'll have a fix soon.


----------



## brumma

Quote: 





anakchan said:


> Talk to V-Moda customer service. I believe they'll have a fix soon.


 
  I'm in touch with them now.  I noticed that Venturecraft has a firmware update.  Hopefully V-Moda will have a similar sort of mail-in program to update the system.


----------



## 10DeeQ

hi, i'm newbie here
  i just browsed through the venturecraft page
  and they are discounting the go-DAP 4.0 with OP2134 from $425 to 175
  now im a beginner here,
  im not audiophile i just want to have a good quality music for me to hear on my spare times
  i just bought v-Moda m-100 headphone (its not even reach yet)
  and i'm already looking for a DAC/AMP
  i will be using my iphone 4s for the source and i don't plant to change it for another 1-2 years.
  i've looked the v-Moda Vamp , and the reviews is quite good
  but at $650 is too much for me.
  so i'm quite confused should i get this Go-Dap with OPA 2134 or i'll be better of with other brand of DAC/amp like Fiio e012 ?
  my budget is $200 the max.
   
 i listened to mostly top 40 songs, 90's pop, sentimental, slows, mellow songs (kenny rogers, kenny loggins, david foster album kind of music),  RnB, Hip Hop, country, and Jazz.
 i don't do rock nor classical
 please guide me here, thank you very much.


----------



## AnakChan

Sorry for the late reply.
   
  I'm like you where my iPhone 4S has been by my side for the past year and will continue so for awhile. I like the integration of the phone with the Go-DAP 4.0 since it feels much nicer as one unit with no cables, or rubber bands holding it together.
   
  The M-100 actually works quite well on it's own off the iPhone however with the Go-DAP 4.0 it improves it further but it's not like night or day difference. It depends on what you are listening to, the quality of the rip, etc. I personally prefer the upgraded Go-DAP 4.0 than the base OPA2134. However the upgrade is somewhat pricier (beyond your $200 budget).
   
  About the Fiio, the E12 is an amp-only? Which means that you're still using the internal iPhone DAC. Most people who look at using external components with the iPhone usually want to bypass the iPhone's internal Cirrus Logic DAC altogether with an external DAC. And for that you need an iDevice compatible DAC (like the Go-DAP 4.0, Go-DAP X, CypherLabs Algorhythm Solo, Fostex HP-P1, etc.). Note that on old iPods, that's a different matter. The old iPods had a very good DAC of which then people would just mod (called iMod or diyMod), and use an external amp only.
   
  For the genre of music you're listening to, I think an external DAC/Amp would be good addition to your iPhone.


----------



## 10DeeQ

hi, thx for the reply it helps me  a lot
  another question i've searched through this forum and the go dap X forum
  and found out that the OPA2134 produced better mid and hi but lacking in the bass
  seeing that you do own the  GO dap X with OPA 2134 and also V-Moda M-100 (which is my only headphone)
  and also considering the type of music that i like,
  will you recommend me to purchase this go dap 4.0 OPA2134 ?
  will the bass on my m-100 reduced significantly ?
  i like my sound to be warm and nice on the Mid, tight and punchy bass without too much boominess, but i also don't really like treeble that too bright and harsh, it makes my listening session very fatiguing.
  and also will this OPA2134 + M-100 combo forgiving enough ?
 most of my songs only AAC 320kbps and some audiophile recording apple loseless so i dont really need a super detail performace out of my music player , i just want a good nice warm sound with a tad boost and punchy bass.
   
  another question is that i read also that the go-dap and v-moda vamp have trouble with the new iOS 6.0
  if i buy now from the venture craft, they will put the latest firmware on it that are compatible with ios 6.0 right ?
  i saw the description on their page the firmware is fw 2.0.1
  i just want to make sure because i did email them yestreday but they havent reply me yet
  and i want to contact them via phone call but i dont know their phone number.
   
  thank you once again


----------



## AnakChan

For the stock Go-DAPs beween the Muses 8820E (on the 4.0) and 8920 and Burr Brown OPA2134, I do prefer the OPA2134 somewhat. However the differences are really quite slight and only when you're critically listening. In the end, both OpAmps aren't my favourite which was why I upgraded my 4.0 to AD83097 being my favourite but VentureCraft doesn't do that anymore due to heat issues (which I've not encountered or experienced) or with OPA1612 which seems to be the preferred OpAmp that V-Moda uses for their VAmp.
   
  I think both with 8820E and with OPA2134, if there's any bass reduction (which I've not noticed but I've not compared between those for a -long- time now) on the M-100, it won't be noticeable. I have to go back to my previous notes but I think I preferred the OPA2134 over the 8820E, but can't remember why. There was another chap who compared between the two earlier in this thread. You may have to go back a few pages though. If you've never used any external DAC/Amps I think you may not find a difference between the two 'cos it's -that- subtle.
   
  About the firmware that is true. You do want to get a Go-DAP that's f/w 2.0x at least. With older firmwares, it still works but it charges the iPhone regardless of whatever mode you put it into. And I normally don't like the Go-DAP charging my iPhone 'cos it lasts for about an hr only. When I have it in "Amp mode" only then my Go-DAP can last for 6-7 hrs.
   
  Who did you mail? VentureCraft or Amazon, etc? Who's offering the discount?


----------



## 10DeeQ

i emailed venturecraft
  as they are the one that have the discount 
  so they indicated that the go-dap that they sell have fw 2.0.1 
  so thats mean it work with iphone 4s iOS 6.01 with no problem right ?
  and i know its been long time since you tried the go dap 4.0 with OPA 2134
  but as i recalled from other thread now you are testing the go-Dap X with OPA2134 ?
  and you also have the M-100
  that's why I'm asking wheter the they both will pair well or not.
  so sorry for too much question
  i'm new here
  and i just only bought the v-moda M-100 after so much good reccomendation here
  and i just thought that the go-dap 4.0 with that big discount is very tempting 
  i just don't want to spend my money in the wrong way as like i told you i'm very beginner
  so i really need other expert opinion, thx
   
  do you happen to have a phone number of the venturecraft that i can call just to make sure about the ios 6 compatibility ?
 thank you.


----------



## AnakChan

fw 2.0.1 was designed for iOS 6.x therefore it should work. I can't say for sure 'cos I don't have an iOS 6.x device. However if call or e-mail VentureCraft I'm sure they'll say it will 'cos that's what fw was designed to address in the first place.
   
  I haven't started actually critiquing the Go-DAP X yet therefore I don't have any comment or thoughts about OPA2134 on that device. I may have to go back to my posts last year to see what I said about OPA2134.
   
  As for pairing with the M-100, on my casual listening on the Go-DAP X, I've not heard anything "bad". To me they both work well but then again, so do the other DAC/Amps I have (such as the CLAS -dB & Rx Mk3), Ortofon MHd-Q7, etc. I've yet to come across a DAC/Amp that the M-100 doesn't pair well.


----------



## 10DeeQ

okay thx
  i think i'll jump to buy it
  hahahaha
  thx for the inputs they really helps me a lot.


----------



## AnakChan

Quote: 





10deeq said:


> okay thx
> i think i'll jump to buy it
> hahahaha
> thx for the inputs they really helps me a lot.


 
   
  No problems. If you like you can PM me and I can talk to them to get them ready about your purchase (and I'll talk to them about your concerns about iOS6, etc.). Should be fine though.


----------



## sensible

Hi, I'm fairly new on this forum so if I did anything wrong, please forgive me.
   
  I'm looking to purchase the Go-Dap 4 but after reading this particular thread, I realized there are various chipsets and each seem to have it own signature (not sure if this is the way to use this term).
   
  I'm planning to use it with my sony ex1000 and westone4, does anyone have a recommendation to which chipsets I should purchase?
   
  My usual music will range between Electro Swing, artists like Nujabes and similar (not sure which genre they're in), Lo-fi, Lounge, Bebop Jazz, Alternative Rock and Indies.
   
  I occasionally listen to dub-step but rarely pair it with my ex1000 or w4, usually m80 with magnum go-vibe (bass setting at max, I love the feeling of the headphone vibrating on my head when I listen to dub-step so it'll be alright to ignore this particular genre.) It would be great if one of these Go-Dap 4 chipsets can let me listen to this genre too.
   
  Thanks in advanced.


----------



## AnakChan

Quote: 





sensible said:


> Hi, I'm fairly new on this forum so if I did anything wrong, please forgive me.
> 
> I'm looking to purchase the Go-Dap 4 but after reading this particular thread, I realized there are various chipsets and each seem to have it own signature (not sure if this is the way to use this term).
> 
> ...


 
   
  Hi, sorry you're late in the game here. To be honest the various OpAmps ("chipsets") is mostly a moot point by now 'cos VentureCraft is actually running out of Go-DAP 4.0 and won't be making anymore. As such they've been having sales on selling whatever remaining stock (all base Go-DAP OPA2134). Therefore the suite of OpAmp offerings have also shrunk.
   
  You may want to see if the V-Moda VAmp still has lots in stock left or running low too. They're basically a custom Go-DAP 4.0 with the primary difference being OPA1612 (nice OpAmp BTW), increased headphone power output increased to 150mw/ch.
   
  Or look at the newer Go-DAP X.


----------



## sensible

Thanks AnakChan, your reply was well anticipated. I guess I'll just have to try Vamp then.
   
  Best Regards to you AnakChan


----------



## 10DeeQ

hi anak chan or whoever that have this go-dap
  i'm curious in what gain setting does yours is running at ?
  
  i'm using V-moda M-100 and an ancient earbud, audiotechnica ath-cm7ti 
  and i'm curious in what the proper gain setting for it ?
 thank you.


----------



## AnakChan

10deeq said:


> hi anak chan or whoever that have this go-dap
> i'm curious in what gain setting does yours is running at ?
> 
> 
> ...


I tend to run on high gain esp with my M-100. I crank up the vol quite a bit. The VAmp actually has more power than the Go-DAP so I don't crank that up as much.


----------



## 10DeeQ

Sorry to be sounded so dumb but can you explain the difference between the hi and lo setting ?
I mean whats the pro,s amd cons?
Currently im on lo gain on my go dap and m100 and even in those setting i never really need full turn on the volume knob to get to the listening volume that im comfortable with.
So do i need to set it on hi?
And whats the pros and cons?
Perhaps a technical explanation on how this work?
 Thank you, im so newbie in this kind of things, thanks once again


----------



## rjklein4470

Ok so I am trying to decide on the Go Dap with the upgrades, or just getting a DX100.  I am just looking for the best sound for my JH 16-pro's.
   
  I also considered just upgrading the JH 16 pro's to JH-3a's and using the iphone.  
   
  Crazy there are so many options.


----------



## AnakChan

Quote: 





rjklein4470 said:


> Ok so I am trying to decide on the Go Dap with the upgrades, or just getting a DX100.  I am just looking for the best sound for my JH 16-pro's.
> 
> I also considered just upgrading the JH 16 pro's to JH-3a's and using the iphone.
> 
> Crazy there are so many options.


 
   
  I think that decision may be easier than you think. Since you've posted in the GD-04 for iPhone 4 thread, presumably you mean the Go-DAP 4.0 and VentureCraft doesn't make those anymore. Nor will they have the upgrades that I talked about back in 2011.
   
  So that leaves you with the DX100 option only unless you're open to other Go-DAP X or Go-DAP DD Socket 1, or other DAP options.
   
  Sadly I've never owned JH products therefore can't comment on the synergy. However I've owned other IEMs of varying brands and have not found any to have bad synergy with the Go-DAP 4.0 (or X for that matter). Mind you though my 4.0s and Xs are upgraded.


----------



## rjklein4470

thank you, I have a lot to learn.


----------



## rckyosho

Quote: 





10deeq said:


> Sorry to be sounded so dumb but can you explain the difference between the hi and lo setting ? these are just gain settings available on most amps
> I mean whats the pro,s amd cons? depends on the phones you using.with low impedance sensitive iems you might get hiss on high setting and volume either go loud to quickly and the opposite for higher impedance full size cans.
> Currently im on lo gain on my go dap and m100 and even in those setting i never really need full turn on the volume knob to get to the listening volume that im comfortable with.
> So do i need to set it on hi? nope as long as your happy with the sound and volume control.
> ...





> Thank you, im so newbie in this kind of things, thanks once again


 
  Words in Red are my answers.
   
  Quote: 





rjklein4470 said:


> Ok so I am trying to decide on the Go Dap with the upgrades, or just getting a DX100.  I am just looking for the best sound for my JH 16-pro's.
> 
> I also considered just upgrading the JH 16 pro's to JH-3a's and using the iphone.
> 
> Crazy there are so many options.


 
   
   
  Quote: 





anakchan said:


> I think that decision may be easier than you think. Since you've posted in the GD-04 for iPhone 4 thread, presumably you mean the Go-DAP 4.0 and VentureCraft doesn't make those anymore. Nor will they have the upgrades that I talked about back in 2011.
> 
> So that leaves you with the DX100 option only unless you're open to other Go-DAP X or Go-DAP DD Socket 1, or other DAP options.
> 
> Sadly I've never owned JH products therefore can't comment on the synergy. However I've owned other IEMs of varying brands and have not found any to have bad synergy with the Go-DAP 4.0 (or X for that matter). Mind you though my 4.0s and Xs are upgraded.


 
  Actually they still have the white version(OPA2134)​ though they have stop production....might be the last unit or last few to clear(reason for the pricedrop to 185usd).They might not offer any upgrades but try emailing them(you never know) cause they have great customer service.IMHO you won't regret getting the Go-DAP unit 4.0(assuming that's what your referrring to) and the money saved by skipping the DX100 can be better spend on more music content or blow it all on the upgrade to JH-3a amp later since I'm guessing your loving the JH 16 pro and the JH-3a is really built for it but using it as a portable just negates whatever subtle differences in SQ unless your using it in a quiet room.


----------



## 10DeeQ

hi sorry to bump this "old thread" but just wondering if anyone here still uses go dap unit 4.0 ?
 will it works with iphone 4s ios 7 ?
 i want to upgrade my iOS but afraid that it might causes trouble with the go dap
 thank you.


----------



## Ehr33

Not sure with the Go Dap. But my iO7 4S work well with my Fostex HP P1 and Onkyo NDS1.


----------



## AnakChan

Ehr33, the HP-P1 doesn't officially and actively charge the iDevice - it's more a side benefit trickle charging.

The Go-DAP 4.0 had an issue in the past that when iOS6 was released the 4.0 would charge all the time regardless of the amp vs I-amp setting. A firmware update by VentureCraft was needed to fix this issue.

I've not tried updating my 4S yet but it seems owners of the V-moda Vamp (pretty much the same thing as the Go-DAP 4.0) seems to work fine with iOS 7 - at least by the Vamp owners. As such I think there shouldn't be any problems with the Go-DAP 4.0 too.


----------



## DrSheep

anakchan said:


> Ehr33, the HP-P1 doesn't officially and actively charge the iDevice - it's more a side benefit trickle charging.
> 
> The Go-DAP 4.0 had an issue in the past that when iOS6 was released the 4.0 would charge all the time regardless of the amp vs I-amp setting. A firmware update by VentureCraft was needed to fix this issue.
> 
> I've not tried updating my 4S yet but it seems owners of the V-moda Vamp (pretty much the same thing as the Go-DAP 4.0) seems to work fine with iOS 7 - at least by the Vamp owners. As such I think there shouldn't be any problems with the Go-DAP 4.0 too.


 
 Both the VAMP and Unit 4.0 now uses firmware 2.0.1 and it is fine with iOS7.


----------

