[Reticuli2]

inserting the Blue Circle Hat Peed Thingee headphone amp into the system as a preamp. This is a $750 headpone amp with preamp outs added (I think) as an afterthought. It does sound quite good as a preamp, with much better dynamics than with no preamp.

In any case, I think you can get good results with a headphone amp as a preamp and save yourself some money.

I notice this with both the teeny tiny in-line Fiio & O2 headphone amps I have if I place them while in zero-gain buffer mode between a beefy mixer headphone jack and an electrostatic amp. The Fiio is sweet & has almost binaural-like imaging, while the O2 is extremely layered, punchy, and natural. The headphone jack just strait to any electrostatic amp, even with the amp way up and the jack way down, sounds very inferior... more confused, imbalanced, worse separation between sounds, worse dynamics, and much less musical. It almost sounds like it's being subjected to a bad compressor. Even just a passive volume control set to around halfway is better than no preamp at all when a good mixer headphone jack is the source. I'm mystified as to why, though, because those two headphone amps are near zero output impedance, and the passive volume pot method is adding a bunch of resistance and probably just slightly rolling off the ultrasonic range even at the halfway point. Does this present an easier load on the headphone jack than the electrostatic amps present?