Well, I have been listening to the HE60 and SR-003 for the past 4 hours non-stop! I have not broken out the Lambda Signature yet, maybe tomorrow afternoon more likely. I have tried them with the following 4 amps:
Woo GES prototype (not up to current specs),
SRM-1 Mk2 Pro,
HEV70 with stax adapter, and
Nuforce Icon with SRD-7 Pro.
To be able to listen to all 4 running at the same time by simply plugging in phones, I have the Apogee mini-DAC XLR out via Neutrik 12" XLR interconnects to Jensens Transformers RCA adapter to anti-cables IC's to SRM-1 Mk2 Pro - then out of the pass through via silver plated copper IC ($60) to the Woo GES. Then I have the Apogee mini-DAC 1/8" line out via Jenna Labs 22g cryo Canare F12 mini-mini to Nuforce with SRD-7 and the Nuforce pre-amp line out via barqy silver plated mini>RCA to HEV70. I already had it set up this way, except that I unplugged the Woo WA6 and replaced it with the GES plugged into the WA6's IC's and Shunyata Viper power cord. I used my Marantza CD5001 via Coax out with a Synergistic Research Digital coax cable into the Apogee.
I listened to Jack Johnson "On and On", FIM XRCD Jacintha "Autumn Leaves", FIM XRCD Tsuyoshi Yamamoto "Smooth Jazz Festival", FIM XRCD "Jazz at the Pawnshop", Diana Krall "Girl in the Other Room" and "This is K2 HD" sampler.
I suspect that the way I have it set up is why the SRM-1 M2 Pro is almost as good as the Woo GES - that maybe the SRM-1 pass through could be holding the GES back slightly (either due to the SRM-1 or the silver plated interconnects which I think are very good but not as good and the anti-cables). Or, it may be the fact that this is a 3yr old prototype GES that is not up to todays build SQ. Or, it could be the fact that these headphones are not hard to drive, and that the better amp will only stand out when presented with a difficult phone to drive, like the SR-007 or 4070. I am just amazed at how well the SRM-1 stands up to the competition. Both amps are quite good sounding with the HE60 and SR-003, but with the HE60 the edge does go to the GES for being the most overall balanced so far.
The Nuforce/SRD-7 Pro has more PRaT and impact, but there is some missing micro-detail and ambience/air with it, making some music sound like it was done in a studio instead of a small venue. In contrast, the SRM-1 Mk2 Pro is filled with air and ambience and detail, but doesn't have quite the punch of the SRD-7 pro. The Woo GES seems to bridge that gap and give more air and ambience than the Nuforce/SRD-7 Pro, but more bass impact than the SRM-1 Mk2 Pro (but it doesn't quite match the bass of the Nuforce/SRD-7 Pro). Soundstage in the GES is well focused in both width and depth, while the SRM-1 seems slightly less focused and smeared but taller.
The GES tames the edge on the highs that I hear in the HE60 with the SRM-1 Mk2 Pro, while the SR-003 benefit from that edge and I might slightly like the SR-003 better with the SRM-1 Mk2 Pro. The GES has slightly less air and ambience than the SRM-1, but I am fairly sure that if I run the anti-cables directly into the GES (and skip the SRM-1) that the sound will get a little more open. The Nuforce adds a little more forwards mids and intimacy as well as more bass, but the treble is closer to the GES and less than the SRM-1 Mk2 Pro. Switching to the HEV70, I get the forward mids and punchier bass of the Nuforce, but with slightly less airy treble and ambience than the GES or SRM-1 (but more than the Nuforce/SRD-7 pro).
I have to take a break from this, and I'll post more when I change the cables around to skip the SRM-1 pass-through. Too bad the GES and WA6 don't have pass-through or pre-amp out.
Now it is Apogee > mini-RCA silver plated copper > Woo. I will also try it with Apogee > mini-RCA solid 1-piece adapter > Anti-cables IC > Woo GES. Then I will also try it with Apogee > neutrik XLR to RCA gender plug > Anti-cables IC.
I will report back late tonight, after my son's baseball game, with the GES and the above connections, using the HE60, SR-Lambda Signature and SR-003. (don't have the Gamma pro here yet).