# RSA F-35 The Lightning Review



## Keithpgdrb

What’s that?  You’d like a review of the smallest fully balanced portable amp in the world?  Why I’d be happy to, here you are my friend.
   
   

   
   
  But before the write up, I must offer special thanks to Ray Samuals for asking me to review his latest amp.   Ray has been a strong leader, supporter, and innovator in the world of portable headphone amps, and his latest entry pushes yet another envelope.
   
  So…  Why another balanced amp you might say?  Doesn’t Ray already make two other balanced amps?  Yes he does, but this one is different, and is aimed at a specific listener, with specific headphones.  more on this later.
   
  The Amp:
  The F-35 Lightning is indeed the smallest fully balanced portable amp in the world to this date, to this writers knowledge.  It measures about 4.5cm wide, 2cm deep, and 9.5cm long (volume knob included).  I honestly don’t see how an amp like this could get any smaller.  Every inch of real estate is used for the plugs and switches. 
   
   

   

   
   
  The amp has the typical rock solid construction and feel of all RSA amps.  All casing is metal including the volume control, and all switches feel solid.  4 screws on each end hold everything together and are nicely flush with the rest of the case.  As with all RSA amps, the power swich is backlit with a red LED when it is on.  When the battery starts to lose power, you can see the power switch fade as well.  I don’t know why, but I like that.  There have been times when I hear the sound breaking up on my RSA hornet and think to myself “damn this recording sucks”.  I then look down at the amp, and the power switch is a pale red, showing me that my recording doesn’t suck, but I am in dire need of a charge.  Anyway, moving on. 
   
  On the back of the amp you have the DC input (used to charge the rechargeable battery), a balanced input plug, single end input plug, and an input selector switch.  As on Rays other balanced amps, you have the option of inputting the signal with a balanced or single ended plug.  This means that you can use a portable player with a simple LOD, or your $25K balanced cd source, both signals will be delivered to the headphones fully balanced.  In Ray’s words, “The lightning, has phase split circuitry that converts a single input signal, fed to the SE input, to a balanced signal”.
   
   

   
   

   
  On the front of the amp you find the volume control, power switch, balanced output plug, and separate gain controls for the left and right channels. The power switch can not be easily toggled while the headphone plug is in.  You must unplug your phones to turn on/off the amp.  So did you notice anything?  What is missing here?  That’s right, there is NO single ended 3.5 output.  You either go balanced, or go home.  This amp is for those people who run their cans balanced, and want nothing to do with the inferior single ended world. 
   
   

   
   

   
  Usability:
  I made mention of using specific cans.  I spoke a great deal with Ray while I was testing the amp in different scenarios.  As this amp is a prototype, there were no instructions or specs to refer to.  I had very little idea what kind of power I was looking at, or what I could expect as far as drivability.  After some experimentation and consultation with Ray, I have confirmed the following. This amp is designed for low impedance headphones like the LCD 2, LCD 3, HE-500s, Grados, Denons, most IEMs, etc. The Lightning is not however designed to drive the HE-6.  If you want a portable amp for that beast, look to the RSA Intruder.  The Lightening can drive the higher impedance cans like the HD600/650/800 to respectable volume levels, but as it is not designed for that, it is not the best match.  I do wish I would have had some balanced IEMs, Denons, or Grados to try with the amp, as I am curious as to how they would perform.  Maybe I will be able to update with that info at a later date.  The majority of my listening was with the LCD-3 and HE-500’s. 
   
  Gain:
  The gain switch has 3 levels.  As per his website, the gain is 3, 6, and 21.  The low gain is used for sensitive IEM’s.  The middle gain is used when a strong signal is fed to the amp.  A good example of this would be the balanced out of a CD player or other full powered source.  The high gain is used when a lower power source like an iPod is feeding the amp.  Helpful if you are driving something like the HE-500.  This is all relative of course because it has a lot to do with how loud you listen to your music.  I found the middle gain fine when using my ipod as a source.  I just needed to turn up the volume pot a bit more.
   
  And now the most important thing…
   
  Sound/Performance:
  For anyone not familiar with RSA portable amps, they consistently deliver full and powerful sound, with a ridiculously small footprint.  The lightening does not disappoint here.  The sound is rich and full throughout the spectrum.  Bass is delivered with authority, and the mids and highs are clear and smooth.  When listening to the LCD 3, well known for its bass performance, I got the sense that not only was the bass quantity and quality excellent, but that it was well supported.  Sometimes you hear an amp that has great attack on the bass notes, but seem to lose steam on the sustained portion.  Not so with the Lightening.  Bass notes ring the way they should.  Not emphasized, just delivered.
   
  Highs and mids are equally represented with effortless support.  Listening to a nice acoustic guitar/vocal recording reveals a beautifully smooth grain and honk free tone, with a nice sense of space.  Soundstage is quite good.  Recordings that put some effort into creating a sense of air and distance around the listener come across with good multi layer presentation.  I believe the headphones to be the only limit on air and space here.  The amp will deliver what you feed it.
   
  Source:
  The quality of your listening experience is defined by the quality of your source.  The better your source, the better the sound.  It really is as simple as that.  People often ask where they should put the bulk of their money when building a system.  Your source should always be the answer to that question.  As such, the Lightening will of course sound better with your $25K balanced cd player then your gen1 ipod.  But then again, you can’t take your cd player on the train.  But there are those who might choose to use their portable amps for everything, so it is important to experiment with all sources.
   
  I did spend a lot of time using the lightening with two different balanced cd players (listed below).  Besides the difference in sound signatures, both did an excellent job and delivered superior sound.  I could be very happy running the Lightening as my home amp.  Are there desktop HP amps that would sound better?  Very likely; But that would be another investment, and a fairly major one to surpass what the Lightening can deliver.
   
  But the Lightening is a portable amp.  It wants to be taken outside, to be part of the world, to let the sun shine upon its face.  So that leaves us with portable sources, and while there are many, most people use either an Apple or Microsoft product.  My listening was done with the 160gb ipod classic with lossless files.
   
  So how did it perform?  I did indeed need to turn up the volume a bit more to make up for the lower power input signal, but I’ll tell you, it sounds great.  The technology involved in converting the single ended signal to balanced works like a charm.  In comparison to the balanced cd players, there is a lot less difference then you would expect.  You have to consider of course the superiority of the DAC’s in the cd players, but that little ipod is representing quite nicely.  As a further test, I hooked up my ipod to my Pure i-20, and ran that into the Lightening.  Much better sound as expected by the nicer DAC.  So, long story short, Lightening performance with an ipod is very good at delivering a solid balanced sound.  About as good as you can expect from an ipod.  This is a pairing I foresee using a lot.
   
  Final thoughts:
  As the latest edition to the RSA portable lineup, the Lightening holds its spot firmly as another great performer.   In an industry where the advantages of balanced configurations are becoming more evident and popular, Ray leads the way with the smallest one on the market.  It performs extremely well with a portable source, and exceedingly well with a high quality desktop cd player or DAC.  I’m not sure how much more you could want.
   
  If balanced is your game, the Lightening should be on your short list. 
   
   
  Equipment used:
  Audeze LCD-3 – Stock cable fitted with balance connector
  Hifiman HE-500 – Moon Audio Silver Dragon balanced cable
  Sennheiser HD-600 – Equinox HD600/580 balanced cable
   
  Meridian 508 CD player balanced out
  Emotiva ERC2 CD player balanced out
  160gb Ipod Classic lossless files – Whiplash Audio LOD
   
  SE Comparison amps:
  Bottlehead Crack
  RSA Hornet
  Grant Fidelity TubeDac-11


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## AmberOzL

Great review mate. I have a question though, I am kinda newbie on these things. So is there a difference in sound when you use the SE input or Balanced input?


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## Keithpgdrb

Quote: 





amberozl said:


> Great review mate. I have a question though, I am kinda newbie on these things. So is there a difference in sound when you use the SE input or Balanced input?


 
  Maybe a newbie, but that is an excellent question, and one that I was struggling with as well.  I struggled, because to test this properly, I needed to have the same quality cable going from the source outputs, which I did not.  I was using an xlr to balanced plug made by Ray, and all I had was a cheap stereo out to 3.5 plug to use as the single ended input.  The other problem was that the balanced out on the source is much more powerful then the rca, so there was a marked difference in volume when switching back and fourth.
   
  having said all that, I will say that I preferred the balanced input in comparison.  I thought the sound had a bit more definition and separation by a margin.  But, I must repeat that the cable I used as the single end input was crap.  I will speak with Ray and see if he can offer any other insight.  I have to call him anyway.


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## AmberOzL

Okay mate, I take your answer like, even if used with SE input, it will sound excellent, maybe slightly lower than excellent.
   
  So, this little item is def. in my list. Gotta check it later on when I save up some money again.


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## Keithpgdrb

The one thing I did not get from Ray was a price point.  No idea where this thing will end up.  Its a niche product for sure.


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## AmberOzL

Well, I am just about to purchase a high end ciem (if my ears are big enough to build it), so anyway I have a lot of time in front of me to save for it. I hope The Lightning won't be a wallet crusher.


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## koiloco

....want nothing to do with the inferior single ended world.....
   
  Great review except for the line above.  IMO, that's a little harsh and exaggerated according to my long time background/experience in pro audio equipment and recording.
  Balanced signals are always good and tend to be cleaner if you're affected by unclean power source and other types of interference... A well-designed amp should not have any problem terminating in SE and still have stellar performance, thus many high end HP amps still only have SE output.  Just my opinion.


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## Keithpgdrb

Quote: 





koiloco said:


> ....want nothing to do with the inferior single ended world.....
> 
> Great review except for the line above.  IMO, that's a little harsh and exaggerated according to my long time background/experience in pro audio equipment and recording.
> Balanced signals are always good and tend to be cleaner if you're affected by unclean power source and other types of interference... A well-designed amp should not have any problem terminating in SE and still have stellar performance, thus many high end HP amps still only have SE output.  Just my opinion.


 
  well, that line was mostly an attempt at irony and humor.  if you include the beginning of the sentence, you see that I am talking about the thoughts of this imagined individual who is committed to balanced cables.  But, having said that, I do not disagree with you.  I love my SE amps, and agree that they can, and do produce exceptional sound.  No disagreement there.  But I do believe that given two setups, where the only difference is balanced vs SE, the balanced configuration should sound better if care was taken in its implementation.  All IMHO of course.  most of my amps are single ended and wonderful.
   
  I do wonder though what my bottle head crack would sound like if it was set up in a balanced configuration.  lol.. but thats crazy.


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## koiloco

Quote: 





keithpgdrb said:


> well, that line was mostly an attempt at irony and humor.  if you include the beginning of the sentence, you see that I am talking about the thoughts of this imagined individual who is committed to balanced cables.  But, having said that, I do not disagree with you.  I love my SE amps, and agree that they can, and do produce exceptional sound.  No disagreement there.  But I do believe that given two setups, where the only difference is balanced vs SE, the balanced configuration should sound better if care was taken in its implementation.  All IMHO of course.  most of my amps are single ended and wonderful.
> 
> I do wonder though what my bottle head crack would sound like if it was set up in a balanced configuration.  lol.. but thats crazy.


 

 agree +100.


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## muzic4life

Looks small but powerful as usual. I wonder how does this compared to something like Intruder...


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## kothganesh

muzic4life said:


> Looks small but powerful as usual. I wonder how does this compared to something like Intruder...



Well looks like the Intruder without the SE's to me.


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## castleofargh

intruder is the usual amp but powerfull, this one seems to be more current oriented than voltage. so ideal for low impedance, current hungry cans/iem.
   
  at least that's what i understand from the different feedbacks, and i would love Ray himself to give us some intels.


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## muzic4life

I also think this could be more ideal for lower impedance cans. But it seems also capable of driving heavyweight too. My intruder is definitely a power monster though.


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## kothganesh

Quote: 





muzic4life said:


> I also think this could be more ideal for lower impedance cans. But it seems also capable of driving heavyweight too. My intruder is definitely a power monster though.


 
  Muzic,
  what cans do you use with the Intruder ?


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## Keithpgdrb

Lightning is for low impedance cans. Read the usability section of the review. It does not sound right with high impedance.


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## muzic4life

I often use Intruder to drive my hd800 (using HPP1 dac output or CLASdb). But it can drive almost anything without any problems. But i prefer to drive my T1 using Portatube. Sound smoother.


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## AmberOzL

About Lightning.
   
  Do you guys think it would pair nice with relatively high output c/iems? Over 100 impedance for example. I am about to get one that's why I am asking.


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## musicheaven

Interesting device Ray came up with, although the lightning is smaller I still prefer the Intruder, the DAC is a bonus to me.


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## musicheaven

I am split on this one. I'd be torn between the intruder and this one but would lean towards the intruder having more functions and working with more headphones and iems; in a way not taking chances with having a shortfall. It is almost like the 71B and Intruder, the line started getting blurred. Just my honest opinion.


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## Keithpgdrb

musicheaven said:


> I am split on this one. I'd be torn between the intruder and this one but would lean towards the intruder having more functions and working with more headphones and iems; in a way not taking chances with having a shortfall. It is almost like the 71B and Intruder, the line started getting blurred. Just my honest opinion.




I Agree. t first, I thought the lightening was just an intruder or st71 without a SE output. I think it has been designed specifically for the ortho cans personally. I don't know what the actual impedance is on the amp. Just that my hd600 was not a great match. I'd rather my hornet for those.


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## kothganesh

keithpgdrb said:


> I Agree. t first, I thought the lightening was just an intruder or st71 without a SE output. I think it has been designed specifically for the ortho cans personally. I don't know what the actual impedance is on the amp. Just that my hd600 was not a great match. I'd rather my hornet for those.



That's right. It is important to know the specs here. If the numbers are right, I'd get the Lightning since I already have the CLAS -dB and the SR 71B


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## muzic4life

amberozl said:


> About Lightning.
> 
> Do you guys think it would pair nice with relatively high output c/iems? Over 100 impedance for example. I am about to get one that's why I am asking.




My guess is should be fine driving iems/ciems (high or low impedance) as i tried some of ray's amps, eventhough they are powerful but it handles iems (including the sensitive one like shure 535) very smoothly (no hiss - black backgroud).


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## AmberOzL

Quote: 





muzic4life said:


> My guess is should be fine driving iems/ciems (high or low impedance) as i tried some of ray's amps, eventhough they are powerful but it handles iems (including the sensitive one like shure 535) very smoothly (no hiss - black backgroud).


 
  Thanks man. I guess I will get something from RSA but not now and I am not exactly sure which model. Anyway Ray's units seem very interesting and high quality. Maybe I will contact and ask his opinion too when I am ready to buy.


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## musicheaven

amberozl said:


> Thanks man. I guess I will get something from RSA but not now and I am not exactly sure which model. Anyway Ray's units seem very interesting and high quality. Maybe I will contact and ask his opinion too when I am ready to buy.




Ray has enough bandwidth for any music lovers, anyway you look at it, you'll be please with the results.


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## AmberOzL

Quote: 





musicheaven said:


> Ray has enough bandwidth for any music lovers, anyway you look at it, you'll be please with the results.


 
  Yeah I noticed that it seems he covered pretty much every area. Out of curiosity, is it easy to order from Europe?


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## musicheaven

amberozl said:


> Yeah I noticed that it seems he covered pretty much every area. Out of curiosity, is it easy to order from Europe?




Best is to ask him, here is his email address and if you have additional questions, ask him. He's one of the easiest guys to reach and fun to talk to.

rsaudio@raysamuelsaudio.com


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## AmberOzL

Quote: 





musicheaven said:


> Best is to ask him, here is his email address and if you have additional questions, ask him. He's one of the easiest guys to reach and fun to talk to.
> 
> rsaudio@raysamuelsaudio.com


 
  Def. will ask him when I save some money again or there is a possibility that my ears are small for the customs I have been looking for, in that case I can buy something cheaper + rsa portable amp. We will see but soon or late I am going to contact him to learn what would be the best for my gear.
   
  Btw, thank you a lot guys.


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## Sonic Defender

I will just throw this out there that the notion of impedance mismatching for lower or higher impedance headphones might be an overblown/over-emphasized consideration. I have now been in two prolonged situations where I had mismatching that if you listen to the threads around here on the subject would lead you to believe that if your equipment is mismatched your sound will be significantly impacted for the worse. First time round I had a Valhalla and HF2 combo for about a year before I sold them. Loved the sound quality and I could not at all detect the horrible effects of the impedance mismatching (except perhaps in one very specific case, but I couldn't confirm the link). Currently I am using my Auditor with almost a 10 ohm output impedance with my Denon D7000s which of course are low-impedance cans. The sound is stellar across the board, really poised, detailed and controlled up and down the frequencies. As far as I can tell these differences in performance due to impedance mismatching are measureable, but that doesn't mean they are audible. When I was first considering the Schiit Valhalla Jason and I exchanged several e-mails on the subject and he told me that he had several clients that were music producers and sound engineers that actually really liked the Valhalla with low-impedance cans.
   
  There is also likely a difference depending on the specifics of the gear. For instance, as the frequency response of the D7000 is fairly tight and not all over the place it would likely not be as impacted by the impedance mismatching anyway, plus the characteristics of the amplification matter as well. All of that is to say that simply saying that a low-impedance headphone will sound worse on an amp that is higher in output impedance is not always going to be true, and even when it is true, just how much impact on sound quality are we really talking about here? I know this is only quasi-related to the original thread, but I felt it was important to mention as the thread adds more weight to the notion of impedance mismatching which I feel is more nuanced and less black and white then it is represented as being. Sorry for thread hijacking, my bad. I am actually considering getting a Ray Samuels design someday so that is why I read threads on his work such as this one.


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## wakibaki

What's the battery life?
   
  w


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## Keithpgdrb

wakibaki said:


> What's the battery life?
> 
> w




In speaking with ray, it remains untested. But if anything like his other amps, it will be quite long. Hopefully he will post stats soon. I can run an amateur test when I return from a trip.


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## castleofargh

Quote: 





sonic defender said:


> I will just throw this out there that the notion of impedance mismatching for lower or higher impedance headphones might be an overblown/over-emphasized consideration. I have now been in two prolonged situations where I had mismatching that if you listen to the threads around here on the subject would lead you to believe that if your equipment is mismatched your sound will be significantly impacted for the worse. First time round I had a Valhalla and HF2 combo for about a year before I sold them. Loved the sound quality and I could not at all detect the horrible effects of the impedance mismatching (except perhaps in one very specific case, but I couldn't confirm the link). Currently I am using my Auditor with almost a 10 ohm output impedance with my Denon D7000s which of course are low-impedance cans. The sound is stellar across the board, really poised, detailed and controlled up and down the frequencies. As far as I can tell these differences in performance due to impedance mismatching are measureable, but that doesn't mean they are audible. When I was first considering the Schiit Valhalla Jason and I exchanged several e-mails on the subject and he told me that he had several clients that were music producers and sound engineers that actually really liked the Valhalla with low-impedance cans.
> 
> There is also likely a difference depending on the specifics of the gear. For instance, as the frequency response of the D7000 is fairly tight and not all over the place it would likely not be as impacted by the impedance mismatching anyway, plus the characteristics of the amplification matter as well. All of that is to say that simply saying that a low-impedance headphone will sound worse on an amp that is higher in output impedance is not always going to be true, and even when it is true, just how much impact on sound quality are we really talking about here? I know this is only quasi-related to the original thread, but I felt it was important to mention as the thread adds more weight to the notion of impedance mismatching which I feel is more nuanced and less black and white then it is represented as being. Sorry for thread hijacking, my bad. I am actually considering getting a Ray Samuels design someday so that is why I read threads on his work such as this one.


 
  I have to disagree.
  you take 2 examples that are monodrivers with pretty stable impedance across frequencies. so the bigger change will be damping that you might or might not notice (or you might even prefer a little less damping, like some do for loudspeakers). on the denon you will get a little sub-bass boost with higher impedance source. as for the the hf2 you will mostly get a boost in high freqs (and that should be clearly audible compared to <1 ohm outputs).
  but I agree this won't be a life changer on both phones.
  on multidrivers you would get some nasty frequency changes due mostly to crossovers.
   
  it is good to trust experience more than forum chit chat, but your case is far from covering all possibilities mate.
  people should be wary of impedance output anyway, there is no bad side effect to a low impedance output (at least sound wise) . when the opposite if not well informed can be a gamble and turn a nice phone into beats.
   
   
   
   to get back on topic, here the question is more about knowing if AmberOzl's IEM will mostly need voltage or current and has nothing to do with the amp's output impedance.
  also I'm confident the lightning's output will be quite low(at least on low gain) and won't be a concern for any phone.


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## Sonic Defender

Quote: 





castleofargh said:


> I have to disagree.
> you take 2 examples that are monodrivers with pretty stable impedance across frequencies. so the bigger change will be damping that you might or might not notice (or you might even prefer a little less damping, like some do for loudspeakers). on the denon you will get a little sub-bass boost with higher impedance source. as for the the hf2 you will mostly get a boost in high freqs (and that should be clearly audible compared to <1 ohm outputs).
> but I agree this won't be a life changer on both phones.
> on multidrivers you would get some nasty frequency changes due mostly to crossovers.
> ...


 
   
  Great perspective, and while I didn't state it before, I am certainly aware that my sample of comparison was rather small. That said, if you notice my point was that the general feel of impedance matching advice here (and elsewhere) would have you believe that it is guaranteed to degrade sound quality in a noticeable way if your gear isn't "well-matched". While I suspect in extreme cases the effects might be very evident my main point is that I suspect much of the time the impact of impedance mis-matching would be measureable/predictable, but not necessarily audible. I like that you mentioned personal preference as it relates to damping, certainly worth considering. Cheers.


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## Keithpgdrb

all I can say is that the HD 600 did not sound good on the amp, but it sounded wonderful on my bottlehead crack.  now, the crack and 600's are almost a perfect pairing, so it may not be a fair comparison.  the he-500 did not sound good at all on the bottle head either.  mismatched.  so. IMHO..


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## estreeter

Keith, my apologies for nitpicking as you've clearly put a lot of effort into this, but given that you consistently typed *Lightning* at the beginning of the review, I'm curious as to how the amp suddenly became the *Lightening* ? The same phenomena occurred when Apple announced their new cable / interface standard for their latest iDevices, and I'm wondering if it's a specific word processing program that is adding the extra 'e' ?


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## Keithpgdrb

The correct spelling is lightning. my apology for confusing you. It doesn't get auto corrected because lightening is also a word. My error.


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## DaddyMojo

Great review and information.  I did not see a price point no your review, is there a price range you can share?


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## musicheaven

It's available on Rays's website.

www.raysamuelsaudio.com 

Under purchasing


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## HeadphoneAddict

Thanks for the review!
  
 I posted my F-35 Lightning Review in the products section:  http://www.head-fi.org/products/ray-samuels-audio-f-35-lightning/reviews/10114
  


> RSA F-35 Lightning
> 
> HISTORY:  My first portable headphone amplifier was the Ray Samuels Tomahawk in 2007.  I needed it because my Shure E4c were not very efficient and needed more power to wake them up or energize them, and my Sennheiser HD600 were much more demanding and needed significantly more power than my iPod could supply - without the amplifier the HD600 felt dull and bland, while the E4c lacked impact and dynamics.  An amplifier transformed them both, and thus began my Head-Fi journey.
> 
> ...


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## JackDiesel

headphoneaddict said:


> Thanks for the review!
> 
> I posted my F-35 Lightning Review in the products section:  http://www.head-fi.org/products/ray-samuels-audio-f-35-lightning/reviews/10114




You mention how there are other amps that sound better than the SR-71B in SE mode, what are they?


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## HeadphoneAddict

jackdiesel said:


> You mention how there are other amps that sound better than the SR-71B in SE mode, what are they?




Well, one that stands out is the RSA P-51, which I stated in my review and I quote below:



> When the RSA SR-71b came out it blew everything portable out of the water when using the balanced output. Although the 1/8" jack was not quite as detailed, open, airy, or spacious as the RSA P-51, the balanced output was noticeably ahead of the P-51 in power and punch with a similar level of transparency. Single ended is very good, but not exceptional like the balanced output.




The P-51 is power-limited vs the balanced Lightning or SR-71b, but has very good sound quality that I preferred over the 1/8" jack of my SR-71b, for the reasons described above. I listened to an RSA Shadow a couple of times and think it was very similar to the P-51. On a similar level is the Pico Slim, but with a little less power than P-51. My iBasso D4 with $60 in opamp upgrades from HiFlight can sound close to the P-51, as does a Meier Stepdance, but the D4 doesn't have a rechargeable battery and had more channel imbalance at low volumes while the Stepdance that I demo'd had too much gain and was too big. As a matter of fact, I've reviewed several of these amps in the past and have always found compromises in one area or another (battery life, or size, or power output, or gain, or low volume channel imbalance, etc). 

So my feeling is that having 2 portable amps with different features and strengths, with one serving easy to drive single-ended headphones and the other serving difficult to drive headphones via balanced output, provides the best option for experiencing superior sound quality with a wider variety of headphones. Whew, that was a long one...

I might say that the SR-71b balanced output sounds like a supercharged P-51, while it's 1/8" jack sounds more like the earlier RSA Predator, with just a little darker, warmer and forward sounding presentation like the RSA Predator. That's still not a bad sound at all, but I'd prefer to own a Lightning plus a P-51, Shadow, or Pico Slim.


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