HEADPHONE tube amp

[Colas LeGrippa]

Hi, I have seen here a couple of schems of headphone amps but before putting money in a project, I'd like to have the opinion of someone who built one with good results. Thanks!

Colas

[triode]

John Broskie, www.tubecad.com, he has an Akido headphone amp that will blow your mind.

If you are not dead-set on tubes, you can build a c-moy for about $30 in parts that will actually
sound really nice. I build them and put them in Altoids tins.

You may also want to check out the headphone amp forums (headwize? I think audioasylum has
one also)... IIRC PRR from here contributes to one of those headphone amp forums.

[Colas LeGrippa]

I 've already visited the HEADWIZE site and saw some schems there, but without knowing how they sound like.

Thanks

[Willabe]

IIRC, fellow member RicharD has made one that he likes. And I think it's posted in the schematics and diagrams section?

http://www.el34world.com/Forum/index.php?board=17.0

             Brad      

[DummyLoad]

John Broskie, www.tubecad.com, he has an Akido headphone amp that will blow your mind.

get the 9pin version of the akkido and use the right tubes, you can drive 32ohm headphones - the octal version won't drive 32ohm headphones.

with 6N1P-EV tubes Zo is claimed to be down in the teens.

--DL

[RicharD]

Attached is the schematic for the one I built.  It hangs off my PC's out put.  I freaking love it.

[Colas LeGrippa]

very cool ! but tell me, where is going the B+ tap identified ''A'' , at 275V ? I just can't seem to find it

[spacelabstudio]

If you are not dead-set on tubes, you can build a c-moy for about $30 in parts that will actually
sound really nice. I build them and put them in Altoids tins.

As long as we're throwing out solid state options, I put one of these in my monitor controller in my studio:

http://gilmore2.chem.northwestern.edu/projects/showfile.php?file=stokes_prj.htm

It's basically the c-moy with a mosfet output stage for better drive, useful for low Z headphones, like Grados.  It sounds great.  But it's not tube.

Chris

[eleventeen]

I know this is a tube amp forum, but I would find it hard to build anything (unless I already had the parts lying around, and maybe even then) when you can buy this 1 x 4 amp/distribution amplifer that will drive 4 sets of stereo headphones for $22.

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=248-6232

[jojokeo]

Are you just looking for something cheap, fast, and easy to build yet sounds good with ear phones for "silent" playing but actually uses one of your own real tube amplifiers?? Plug your own tube amp's speaker output directly into this instead of the amp's normal speaker and you have your tube amp become a quiet headphone amp.

http://www.el34world.com/Forum/index.php?topic=11404.msg105451#msg105451

[RicharD]

very cool ! but tell me, where is going the B+ tap identified ''A'' , at 275V ? I just can't seem to find it

The A tap goes nowhere.  My PT has more B+ than necessary.  The 6DJ8 is a relatively low voltage tube.  That PT was something Dummy Load had laying around. 

[Colas LeGrippa]

I see. I find the schems interesting and I would be ready for a prototype. Do you have specs like distorion % , range of frequencies, output impedance , voltage and power ?

Thanks

Colas

[RicharD]

I never measured distortion or response or anything like that but it sounds great to my ears.  Truth be told it's pretty much a direct copy of the Morgan Jones "modified" amp.  The circuit to the left is superfluous whereas it's simply a preamp gain stage for my power amp.  I wanted separate level controls for my mains as well as my headphones.  This unit hangs off my DAW.  I leave the PC via SPDIF into a California Audio Labs D to A converter.  That feeds this circuit.  The preamp feeds a Hafler DH220 into a pair of studio monitors.  The headphones I drive are Beyer Dynamic DT770's.  I've had up to 3 sets of headphones connected at one time w/o any issue.  More than loud enough.

[Colas LeGrippa]

my old CAL cd player has died long ago.I miss it. Well, if you are really please with the amp, I'll build one. Get back to you once completed. Thanks

colas