[d.phens]

How about modifying T-Amp or an old tube amp to become a headphone amp?
Adding output capacitors to match the one of the headphone, but what else is needed?

 

[d.phens]

I'm interested in making a sort external of transformer box to plug the speaker wires into, with headphone output. Possibly with crossfeed too.

 

[cotdt]

you can do it with any speaker amp except the T-amp. The T-amp is pre-bridged so you can't combine left and right channels. that means you'll have to make all your headphones dual mono. furthurmore, you'll have to use a different output filter circuit for each different impedance headphone. Sure, you can use resistors on your headphones, but it's so un-elegant and degrades sound quality. The T-amp is also too noisy for headphone use, unless you like listening to background static. so you end up having to put in a lot of work for an inferior amp.

for any other speaker amp, all you have to do is lower the gain. but be careful, some are not stable with too low a gain. you might want to add a volume pot if it doesn't already have one.

 

[d.phens]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif you can do it with any speaker amp except the T-amp. The T-amp is pre-bridged so you can't combine left and right channels. that means you'll have to make all your headphones dual mono. furthurmore, you'll have to use a different output filter circuit for each different impedance headphone. Sure, you can use resistors on your headphones, but it's so un-elegant and degrades sound quality. The T-amp is also too noisy for headphone use, unless you like listening to background static. so you end up having to put in a lot of work for an inferior amp. for any other speaker amp, all you have to do is lower the gain. but be careful, some are not stable with too low a gain. you might want to add a volume pot if it doesn't already have one.

I suppose I could unsolder some mysterious things inside the T-Amp
(don't know which yet :-D ) to remove the bridging.
Moreover, decreasing gain using capacitors would probably reduce all the hiss. Huh?

Thanks...

 

[d.phens]

Moreover, lots of headphones have 4 wires.

Anyway I could have one custom balanced wire for all my headphones (I'll never keep a bunch of them) which would be modded to have i.e. female minijack on them to fit that custom cable.

 

[xenithon]

There's always the Antique Sound Lab UHC Signature

Dubbed as an "amplifier to headphone amp transformer", it does exactly what you'd require without any modification requirements.

 

[mono]

T-amp works fine for headphones contrary to cotdt's claim of excessive noise and "un-elegant". There is no "elegant" use of a speaker amp for headphones if one had to mod it. I tend to avoid use of the word elegant though as it usually comes from a person in a context where they arbitrarily think something that suits their own subjective goals or ideals best, is automatically a better choice for others too.

I already asked cotdt to link a couple people who have tried the T-amp and found it a problem but thus far nothing. People HAVE done it and liked the result so all evidence points to it being an option though it is true you can't bridge the grounds, have to mod the headphones and add/change the output filter. With other amps having common ground it is often just a matter of putting some resistors, say 100 ohm in series on the L/R outputs, but it really depends on the gain of the amp and the cans you'd use, to retain best use of the volume knob travel vs loudness.

I tend to think that modifying the headphones is the biggest detraction, as you'd then always need an adapter to use them with any amp having a normal 1/8 or 1/4" jack, or swappable cords with different plug wiring, the other end plugging directly into the can cups.

However, many would consider it better to just put a small headamp into the power amp case instead of resistive limiting of the signal, having a typically lower resolution sound than would be had with a proper headamp.

 

[F107plus5]

Quote:

Originally Posted by xenithon /img/forum/go_quote.gif There's always the Antique Sound Lab UHC Signature Dubbed as an "amplifier to headphone amp transformer", it does exactly what you'd require without any modification requirements.

Hey! That looks a lot like HD600s shown there!

Using a receiver is a wonderful way to route all the different sources and even have some EQ adjustability if the final SQ is reasonably high.

I wonder.

I wonder if one of those guys on my receiver speaker outs, and the phones in the headphone jack is a thought? I suspect my low impedance phones are happier with the jack and the high impedance ones on the box.

Gotta find out more about these puppies!

EDIT: Did a search and found the Grommes HS-600 too; but it doesn't seem to be in production any longer.