OK, enough testing for tonight.
Of all the equipment lent to us by Headroom, and the limited stuff I own, here are my impressions:
Amps:
Little amplifier: good value, small space.
Max: Quite good!
Blockhead: overkill for most.
The amps aren't exactly my tastes, since I like more midrange and bass bloom, and a slightly less-forced treble.
I would love to see if the Perreaux holds its own against the Little or the Max, since the Perreaux is rather inexpensive, yet uses discrete transistors (no opamps, IIRC).
Headphones:
Grado RS-1 balanced: I don't like these. I own a pair of SR-125s, which seem good value for money, especially because they run on my portable devices without an amplifier rather well. But, I can't see paying more for Grados of this generation. Perhaps the older ones, but I doubt they are different enough to win me over. The RS-1 had thin sound with noticeable colorations, impotent bass, harsh textures (intermodulation distortion, it would seem), forward in-your-face (head, actually) perspectives, and not even able to place images relative to each other (woodwinds vs brass, for example, which are clearly placed on other transducers).
HD600: Not bad at all. Much superior to the RS-1. A bit bright on top and thinned out or blanched in the midrange, but not too bad. If I owned them, and wasn't dissatisfied, I don't think upgrading to the HD650 would haunt me.
HD650: A good step up from the HD600 (judged here with the same Cardas balanced cable), but not as big an improvement as the jump from RS-1 to HD600. Midrange now matches the bass and treble, both in quantity and in character, with smoother response and lower distortion throughout. Not a perfect electrostatic-like coherence, but really close. nice dynamics, including orchestral tuttis with bass that mangled the RS-1s. Imaging was above/forward of my head (not in it, or behind it, as with the RS-1). A nice illusion of sound outside my head in the room, but not enough to be fully convincing compared to speakers, especially at hard left or right sounds. Central images are nicely placed, with good depth layering, and good angular placements of sounds placed at small and moderate angles from center, too. I haven't heard better soundstaging on headphones. Personally, I don't get the dreaded three-blob sound on any headphones (perhaps my particular ears).
With the stock cable, the overall sound is a bit less transparent, with less audibility of the far corners of the stage or even the space around instruments. Timbres are a bit damaged, and timbral textures are slightly coarsened with low level information getting a bit lost in the smear. Even with these criticisms, if money were tight, I'd live with the stock cable and buy the HD650s (as opposed to a lesser can with better cable), knowing I could get a cardas cable later. I'll be getting one sooner, myself... but an unbalanced one.
Connectors on the HD650 and 600 were not a problem. They were firmer on the HD650, but after the first removal (it took a bit more force than I'd have thought, but not excessive), I found it easy to change cables quickly.
Best bargains? I think the HD650 is the big winner. And Cardas. I would not like a cable that is any brighter than Cardas, however, or "faster" or whatever adjective one could come up with.
I also found the Little rather good for only $260. One can also upgrade that amp. I'll have to ask Ivy if this loaner has the premium module. I believe the power supply is the base module.
I can't call the Max a bargain, and I'm not even sure how it compares with other $1600 amps, but it is certainly worth auditioning.
I think the Perreaux may have a less bright presentation, warmer and easier on the ears, without any treble exaggeration, this based on comparison of each against my SCD-XA777ES headphone output. The Perreaux may be more realistic and less sensationalized. I recall separation of images and timbres and textures were quite nice, a good improvement over my 777's output in all these dimensions. In contrast, the Headroom amps, perhaps higher-resolution and more solid sounding, were a bit less pleasing than even the headphone out of my SCD-XA777ES, and no less bright -- something that concerns me -- despite the obviously better resolution and extension.
Someone, please bring a Perreaux SXH1 and a Singlepower MPX3 to the meet!
