I use a Darkvoice 332 to power my HD 650s, it´s a fantastic combination!
The Gilmore guts:
Simple.
Because it sounds good. All I can tell you is this amp sounds much better with my AKG K601's than some of the op amp headphone amps I had used previously to it. I used to have a Cmoy amp, which people recommended earlier in this thread. It sounded terrible compared to the Gilmore.Way over the top. Why make your own op amps out of transistors when there are extremely high quality op amps out there, with circuits that don't require a ton of 1% tolerance resistors and and two trimpots per channel?
Because it sounds good. All I can tell you is this amp sounds much better with my AKG K601's than some of the op amp headphone amps I had used previously to it. I used to have a Cmoy amp, which people recommended earlier in this thread. It sounded terrible compared to the Gilmore.
You can go on and on about the technical aspects if you enjoy it. The reality was I compared this amp to two other op amp based headphone amps I had, a Cmoy and a Pimeta, and the Gilmore blew them both away. More dynamic, more detail, more enjoyment.An op amp is just a clump of transistors, pretty much. The output impedance of whatever circuit used is probably the biggest factor that will vary the audible qualities between different units, and probably the most important to get right, and correctly matched to your headphones. Op amps and transistors can both be used, but it's likely to come down to fifty cents worth of passive elements on the output side.