# My DIY headphone tube amps



## Artsi

It's a little dubious to start thread about my DIY amp, since i'm not any pro with these electric things. Just have made couple working headphone tube amps before this. 
  
 So here is photo of my contraption with 6080WC tubes.

 And here is schematics for one channel.

  
  
  
 As you can see it is simplified from some schematics from internet.
  
 And what a mess it is inside.

  
 Box is little too small for this kind of amp. Cast aluminium Hammond 1550J 275x175x63mm.
  
 B+ supply is made with full wave bridge rectifier. After that is 1H 300mA choke and then two parallel 1000uF 250v capacitors. After that there is 1000uF's for each channel loaded with 68ohm resistors. Heaters have also DC with 22000uF capacitor. 
  
 Volume potentiometer is ALPS 100k stereo LOG. Transformer is inMADout TA34M100.
  
 Amp works perfectly with 6SN7's as powertubes too. Driver tubes run very low power, I think 470ohm resistors could be as low as 270ohm, but how much this could add amp output power, i do not know. Also from 6AS7's could take much more power with lower resistance resistors, but i have not needed more power. Total power consumption of amp is around 85w with 6SN7's and 6080's.
  
 At least i'm very happy that this thing works without hum and measured frequency response is totally flat between 10-20000hz. Now i just need more tubes to roll.
  
  
I DO NOT SUGGEST BUILDING ANY TUBE AMP WITHOUT ANY EXPERIENCE OR UNDERSTANDING. Voltages inside these amps are pretty much lethal.
  
 Edit: changed something to schematic. 6AS7 anode resistors from 270ohm to 150ohm.


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## superdux

Artsi it looks fantastic!
 I'm not into electronics but when i see creations like these i'd love to get off my lazy bum and do some learning, lol.
 Instead i can only admire the work you and the DIY folks do.


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## TrollDragon

Exellent Job!
  
 It's hard to fit everything is a small case but you did a great job with that space.


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## Artsi

Here is photo of this amp with russian 6N13S and 6N8S.

 There is brown tape round the bases of 6N8S that they do not mix with other same tubes. '73 6N13S tubes sound far more better than rather new Philips ECG 6080WC's. I was little disappointed about sound when i listened it with 6080WC's, but problem was only with powertubes.
  
 Here is photos of some amps that i have made.

 Amp for four 6SN7's
  

 And pan-amp with 6A6 as driver and 6SN7's as powertubes.


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## TrollDragon

Excellent, I just love the look of the 6N13S's!


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## i luvmusic 2

That is one good looking AMP.


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## nikongod

Neat amp!
How much current does the output stage pass?
Have you thought of swapping the "top" 6sn7 for a SS CCS?


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## Artsi

nikongod said:


> Neat amp!
> How much current does the output stage pass?
> Have you thought of swapping the "top" 6sn7 for a SS CCS?


 
 I'm not good at calculating those mA's. With 6080 tube cathode resistor is 220ohm, Voltage after this is around 17 and between this and another triode anode is 106v difference.
  
 And what does SS CCS mean?


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## nikongod

V=I*R
Volts=current*resistance
Algebra:
17V/220ohms=0.077A=77mA

SS CCS is a solid state constant current source. You could get down to 3 bottles that way, and possibly improve overall performance. 

In any case, maybe just for the next one. It is quite cool to see a 6as7 working like this. Very cool.


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## Artsi

nikongod said:


> V=I*R
> Volts=current*resistance
> Algebra:
> 17V/220ohms=0.077A=77mA
> ...


 
 I like how this amp sounds as is. Perhaps with next amplifier i'm going to use rectifier tube to make things even more oldschool.


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## stupidmop

Nice! Drooling  Thanks for posting


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## Artsi

stupidmop said:


> Nice! Drooling  Thanks for posting


 
 No, thanks to you for your kind words.
  
 Been listening diligently this my newest amp and i have came more and more pleased with this beast. Been listening mostly with pairs of Russian 6N8S '65 and Philips ECG 6080WC and i have newer heard this kind of evolution in sound. Could even capacitors get better with some usage... My initial impressions for these 6080WC's were very bad and i tried to avoid listening with these, but in the end i had to use these, since one of my 6N13S tube is not working perfectly.
  
 Amp is totally silent from 0% to around 60% volume, and after that there is audible electric interference noise. This does not bother me, since my normal listening levels are around 20-40% volume.


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## Artsi

I have made couple amps more.
  
 First this round cute amp. 6X5 rectifier, 2x6SN7 and 6SL7. 

 Hope my wife takes this on her desk...
  
 And next this little amp. 6X5 rectifier, 2x6N6P and 6SL7/6SN7 driver.

 And photo from inside. Not much room for more parts.

 One could be thinking what is that "volume" knob on amp. It is feedback (gain) adjuster.
  
 Both amps are insanely good sounding.


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## TrollDragon

Nice, very Nice!
The bottom amp looks great, I had a look at that chassis in the Hammond catalogue and yes it is compact!

Love the power button.

Whenever you are tired of that one feel free to ship it my way.


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## Artsi

trolldragon said:


> Nice, very Nice!
> The bottom amp looks great, I had a look at that chassis in the Hammond catalogue and yes it is compact!
> 
> Love the power button.
> ...


 
 It seems that i'm not going to get tired with this one in the near future. 
	

	
	
		
		

		
		
	


	



  
 Now look at this

 RCA 6AS7G as a *driver tube*. Surprisingly it sounds amazingly good! Gain is much lower, but this amp is otherwise so sensitive, that i get easily enough power to my headphones.
  

 Rare ECC230 tube is a driver tube too. 
	

	
	
		
		

		
		
	


	




 
  
 I have also octal to 6DJ8 and octal to 12AX7 adapters, so i can use many many different tubes with this one. Waiting impatiently 6BX7GT and 6BL7GT tubes to arrive soon. They have gains 10 and 15.


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## jww187

The amps look great!  I'm just starting to think about my first build, some great inspiration. subscribed.


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## Artsi

Building new amp. Weights already over 10kg. Power Transformer is from that rather ugly 6SN7-6AS7 amplifier. With this amp that transformer looks much better.

 Still waiting for 6BY5G rectifier tube. RCA 6SN7GT tube is just there for photography. This is going to be "normal" stereo amplifier with headphone output too.


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## whirlwind

Great looking amps.
  
 Very nice job.


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## elmoe

This is such a cool thread.


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## i luvmusic 2

Very nice.


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## TrollDragon

Looking Excellent Artsi.
I see some commercial products in the future, The Artsi Line of Exquisite Amplification.


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## Artsi

Some progress. Don't know where camera found that greenish color...


  
 I left some space for future improvements, like another RCA line in and more switches. Tomorrow i could begin soldering parts inside with my 15y old cheap soldering iron and that is much more fun than making chassis with not so proper tools. Drilling holes for tube sockets was easy with my new step drill. First i was going to paint plates, but after seeing amp outside ready i gave up on it.


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## Artsi

It works \o/ ! 




  

 Newer 6BY5GA rectifier tube does not look that bad. It does have pretty strong glow. I also have older coke bottle model 6BY5G.
  
 There is relay that disables speakers, if headphones are inserted. I have to be careful not to burn my headphones accidentally, this amp is capable to do that. Need to find a way to lower gain if headphones are inserted.
  
 Frequency response seems to be flat between 10hz-20khz, so everything is working as expected and inMADout output transformers seem to be very good for the price.


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## elmoe

Looks great!


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## i luvmusic 2

artsi said:


> It works \o/ !
> 
> 
> 
> ...


 
 Nice work as always.


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## stupidmop

Artsi you are blowing my mind with all these builds.


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## bdiz

Some fantastic amps, I'm more or less worried about causing a fire and burning down my apartment. 
 Good Job guys!


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## Nhubley

Nice job keep it up man!


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## lamode

Looks much better than any of my DIY projects


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## Artsi

I have build new amp. Just basic stereo amplifier without headphone connection.


 470uF 450v capacitor is shared to both channels. All transformers and choke is from old Hammond organ amplifiers. Output transformers are originally for bass, but they seem to work excellent as full range transformers. There is small switch behind powertubes to choose from triode and "ultra linear", but i do not publish how i made it without UL-taps. Input selector is also from old hammond for 4 rca inputs.


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## mahelun

artsi said:


> It seems that i'm not going to get tired with this one in the near future.
> 
> 
> 
> ...



 


Just wondering how much did it cost you to build it? and will you sell it in the future XD. Looking awesome haha..


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## cowneko

artsi said:


> It's a little dubious to start thread about my DIY amp, since i'm not any pro with these electric things. Just have made couple working headphone tube amps before this.
> 
> So here is photo of my contraption with 6080WC tubes.
> 
> ...


 
 Thanks a lot Artsi for sharing this built, I'm really interested to build one myself, I just need a clearer wiew of the PSU side as it will be my first PtP build.
  
 I shall make a photo WIP of the build, as it may help others too.


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## cowneko

Well I took a little time studying the schematic and photos of Artsi's build.
 I came up with a complete schematic (amp section and Psus) but I'm still wondering about the res and cap in parallel with the two 1000uf 250v caps, I think the res is a bleeder but not sure about it's value, the poly cap seems to be a way to reduce ripple but no idea of it's value or real usefulness.
  
 If you see anything odd please let me know.
  
 http://i1342.photobucket.com/albums/o769/cowneko/6sn7_schematic_zps9f2wxjuq.png
  
 http://i1342.photobucket.com/albums/o769/cowneko/built_legend_zpsyqkpoi2s.png


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## DutchGFX

What brand power transformers do you use? It looks like Edcor, but I had terrible noise on the one transformer I got from them, so I use Hammond nke for my builds. Should I give Edcor another shot?


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## cowneko

dutchgfx said:


> What brand power transformers do you use? It looks like Edcor, but I had terrible noise on the one transformer I got from them, so I use Hammond nke for my builds. Should I give Edcor another shot?


 
 Seems like you're talking about the Tubelab SSE witch is present in my photobucket library, if that's the case, yes the OPT are Edcor (CXSE25-8-5K) the Power tranny is a Hammond 374BX (good transformer but tend to heat up quite a bit).
  
 The Edcor are superb, no noise whatsoever, just great overall response, big bass. I can't recommend them enough in regards of their price/performance ratio. I don't know about their Power tranny performance, but they seem great.
 For the Head amp I don't really know witch tranny to use yet, I'll have to know the overall load of the amp to choose a right one (the InMADout one seems overkill for the project, but I could be wrong)


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## tomb

dutchgfx said:


> What brand power transformers do you use? It looks like Edcor, but I had terrible noise on the one transformer I got from them, so I use Hammond nke for my builds. Should I give Edcor another shot?


 
  
 In my experience, Edcor's bad PTs run about 1 in 30.  The other 29 in that ratio are completely silent.  So, yeah - I would give them another chance.  I haven't had direct experience with Hammonds except for their chokes, but from someone who knows - the Hammond PT's are inherently more noisy than Edcor.  IOW, a perfect Hammond is not going to be as quiet as a perfect Edcor.


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## DutchGFX

cowneko said:


> Seems like you're talking about the Tubelab SSE witch is present in my photobucket library, if that's the case, yes the OPT are Edcor (CXSE25-8-5K) the Power tranny is a Hammond 374BX (good transformer but tend to heat up quite a bit).
> 
> The Edcor are superb, no noise whatsoever, just great overall response, big bass. I can't recommend them enough in regards of their price/performance ratio. I don't know about their Power tranny performance, but they seem great.
> For the Head amp I don't really know witch tranny to use yet, I'll have to know the overall load of the amp to choose a right one (the InMADout one seems overkill for the project, but I could be wrong)







tomb said:


> In my experience, Edcor's bad PTs run about 1 in 30.  The other 29 in that ratio are completely silent.  So, yeah - I would give them another chance.  I haven't had direct experience with Hammonds except for their chokes, but from someone who knows - the Hammond PT's are inherently more noisy than Edcor.  IOW, a perfect Hammond is not going to be as quiet as a perfect Edcor.




Im only on my third build, but I certainly am avoiding OPT's in the future since they cost an arm and a leg. However, if the edcors sound good I may give them a try. I used Electraprint OPT's before and they sound amazing, but they cost around $300 so that kind of sucked.

I was concerned with the power tranny. I have an escort that has really bad mechanical noise. I have used 2 Hammond's, both of which were silent. I have another Hammond coming for my next build, but maybe I'll try Edcor again.

How come noone uses Antek? I thought people preferred toroidal...


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## cowneko

dutchgfx said:


> Im only on my third build, but I certainly am avoiding OPT's in the future since they cost an arm and a leg. However, if the edcors sound good I may give them a try. I used Electraprint OPT's before and they sound amazing, but they cost around $300 so that kind of sucked.
> 
> I was concerned with the power tranny. I have an escort that has really bad mechanical noise. I have used 2 Hammond's, both of which were silent. I have another Hammond coming for my next build, but maybe I'll try Edcor again.
> 
> How come noone uses Antek? I thought people preferred toroidal...


 
 It really depends on the application. Toroid trannies have a far higher primary to secondaries capacitance, hence more noise than EI trannies, it's true for power transformer but even more for OPT trannies. For Power transformer you can deal with the noise by adding more filtering at psu stage, but for OPT, the toroids needs special winding technics to lower their capacitance. Good trannies for audio can be found from TOROIDY ( I know antek are making audio toroid too but they are harder to obtain in Europe), they make PP and SE trannies as well as power transformers and they are really good (and not that expensive if not chosing the boxed models).
  
 The second reason for using EI transformers is the good old fashioned look 
  
 I might use Toroid myself for the OTL amp.


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## tomb

dutchgfx said:


> cowneko said:
> 
> 
> > Seems like you're talking about the Tubelab SSE witch is present in my photobucket library, if that's the case, yes the OPT are Edcor (CXSE25-8-5K) the Power tranny is a Hammond 374BX (good transformer but tend to heat up quite a bit).
> ...


 

 PT means Power Transformer.  Not sure which post you were addressing, but I was not referring to OPTs.


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## DutchGFX

OPT - output transformers


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## SirIsaac

artsi said:


> It works \o/ !
> 
> 
> 
> ...


 
 This looks beautiful, nice work.


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## mateusfig

artsi said:


> It's a little dubious to start thread about my DIY amp, since i'm not any pro with these electric things. Just have made couple working headphone tube amps before this.
> 
> So here is photo of my contraption with 6080WC tubes.
> 
> ...


 
  
  
 Thanks for this!
  
 Do you have a circuit board for this project? I would like implement this using a board. If you have this, please send me the project files.


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## i luvmusic 2

This thread inspired me to build my own,Here is the beginning these cost me $99 canadian PESO including tax.
  
 THANK YOU ARTSI!


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## i luvmusic 2

Here is the finished amp.....


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## HiGHFLYiN9

Very nice. That's a heck of a switch, what does it do other than turn on the power? I like the throw-back tube sockets, just like Dynaco used to use. I also appreciate how no real estate is wasted inside the case. Anyone who's lived in a small dwelling can appreciate trying to maximize space  

Also, what do you think of the Mundorf electrolytics? They're usually 3x the price of comparable Panasonic/Nichicon, just curious if you found them to be worth the jump. I've picked up a couple for the power supply of an Aleph J I hope to build in the future, but don't have any comparisons just yet.


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## i luvmusic 2

Thanks!The switch is 4PDT ON OFF ON to switch from 6.3VAC to 12.6VDC for the 6SN7/12SN7 tubes heaters UP position is 12.6VDC and down is for 6.3VAC and on top of the chassis it have a LED VOLT METER for the 12.6VDC output For the CAPS i have none of those caps you mentioned  so i can't do a comparison.I have a kit that i build many moons ago this one have mostly FILM CAPS all MUNDORF comparing this kit to  these AMP that i just finished they do sound very similar so i guess those MUNDORF Electrolytic CAPS does a good job.Talking about maximising a space,Did you noticed their is no VOLUME CONTROL?I ran out of space for it LOL


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## whirlwind

This is a great thread....great job guys.


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## i luvmusic 2 (May 29, 2017)

Thinking of building a PREAMP...

Oh boy this hobby.


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## i luvmusic 2

Here is the preamp that i just finished.



 

 

 

 

 

 

 

 


And of course the rats nest


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## pezbot

What kind of transformator and and powersupply would you guy's recomend for this?
I live in Norway and have 230vac from socket




Artsi said:


> It's a little dubious to start thread about my DIY amp, since i'm not any pro with these electric things. Just have made couple working headphone tube amps before this.
> 
> So here is photo of my contraption with 6080WC tubes.
> 
> ...


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## Kitchener

This thread is pretty much DIY porn.

I’m nurturing a fantasy of one day building my own stereo amp.

Thing is, I know nothing of circuitry and my only experience with DIY electronics comes from building a Crack and some keyboards.

Can’t read schematics worth a damn.
-I can recognise resistors, caps valves and trannies but it’s like recognising words in a foreign language.
And the maths behind the Watts, Volts, Amperes, Henries, Ohms? Not a clue.

But I’m decent with a soldering iron.
And a desire to learn goes a long way, I’ve heard.

Is there any literature any of you would recommend to a neophyte or some handy guides that could set me in the right way?


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