It's the Headamp Gilmore V1 (early dynalo implementation); the very first amps Headamp ever produced. The audio circuit should be nearly identical to the V2. The V2 got a custom case, but V1 has the PSU in a separate chassis, which is nice. Years ago I remember some who owned both amps preferred the sound of the V1 over the V2. Either way, I still have a V2 and it's very good. Nice amp worth holding onto and using. Should kick the crap out of a lot of (most of?) today's amps. Don't expect it to fatten up the tone or make a bright/lean source sound good, though.
I know it will sound excellent with the Sennheisers on a good analog rig, and I also know it will do a superb job driving the Audio-Technica L3000.
Perhaps a (largely) unheralded classic. The headphone amp market moves too damn fast these days, and not for means of improved sound quality, it seems. Though I'll bet the newer headamp stuff sounds even better. The most recent Headamp I've heard was a Gilmore Reference (years old now), and that thing was crazy good. Almost good enough for a tubes & speakers convert like me to keep it :)
A good upgrade would be to look into replace that Alps blue pot with a stepped attenuator - if you can find one that fits and if you can live with the discrete volume steps in 2-4 dB increments.
Edited by mulveling - 8/30/10 at 5:28am
