I have a BUDA and use it to power my LCD-3's. It's part of a dedicated Triple Stack setup that I use with a Squeezebox Touch.
I also have a loudspeaker system with a turntable, tube preamp/phono stage, an SACD player, and another Squeezebox Touch.
Of course, the triple stack setup has the advantage of being balanced end to end. The Squeezebox connects digitally to the UDAC, and it's all balanced from there. My SACD player and preamp are both single ended, while my Krell power amp does have balanced inputs.
What I'd like to is use my LCD-3's in my main system, so that I can listen to my vinyl collection and SACD through the cans. I don't particularly mind giving up having the headphones and main system as two completely separate setups, my loudspeaker system is in a dedicated 2-channel room and I'd be just as happy listening to the LCD-3's in there.
So what I'd like to is feed a headphone amp through my preamp, which has dual outputs.
Being that I already have the BUDA and love how it drives the LCD-3's, I'd be perfectly happy to use that (along with the DPS), although I wouldn't be running the headphones balanced at that point. I should be able to sell the UDAC pretty easily, as well.
However, I've always been a bit wishful that non-portable headphone amplification would move the way of separate components in the loudspeaker world, and take on an amp/pre-amp design. So the amplifier would simply be an on-off switch, without a potentiometer. The pot would be in the pre-amp.
By having the volume control built into the amplifier as all headphone amps that I know of do, if I want to source from a pre-amp as I do, you have two volume controls in the signal path.
So I guess my first question is whether or not I should keep the triple stack in the first place, or if I'd be better off selling all three pieces of the stack and starting from scratch, using the funds from the sale to buy something completely new (and presumably single-ended), or if I'm better off keeping the amp and the power supply to use here and just sell the DAC?
Second question, and this really applies to any amp I would use in this application, is whether or not it would be advisable to eliminate the pot in the headphone amp by simply using a jumper to short it out of the circuit. This would not be a permanent modification as the jumper could always be removed. At this point the headphone amplifier would function at full volume, and I would be relying on the preamp's volume control to make sure I don't blow my ears off.