More comments...I have a few more comments @ around 25 hrs of burn in or so.
More so than the 600's when I first got them, I can really get a sense of these can's potential. I've been listening to them for a few hours today as they have been progressing through the burn in cycle and it is most interesting; I can actually hear the sound changing, and then seemingly changing back to a less resolved state. I notice this most in the midrange where I feel many of the burn-in refinements will take place. When the headphone is performing though, words like intimate, and sensual definitely come to mind. At first I thought I was imagining this since we are all pretty susceptible to placebo in the headphone/headphone amp world, but I played a familiar track on Mark Knophler's new DVD-A and it did indeed oscillate a bit.
I also finally got to try out the HE60/HEV70 today, got a good stepdown transformer from... Raidoshack! hahaha, I was pleasantly surprised. Not with the Combo! But with Radioshack. I walk in and there are these two relativlely ditsy girls working the counter and no offense but I was hesitant to ask them anything. As it turned out, amazingly, the one I asked was quite knowledgeable saleswomen. She showed me the right transformer, told me why, and when I said it was for headphones, showed me another with the correct Watt Handling Stage, and she actually wanted to hear what the fuss with an $800 pair was all about! Haha!, nevermind I already have a girlfriend, but that was surprising.
Anyway, the headphone (HE60/HEV70) sound very nice to me. I do not think, as most have already said, that this headphone is at its peak with this amp, but comparing it to the HD600 is very informative. I would say that this combo currently in many ways IS better than my HD600 (cardas) out of my RP6, but in many ways it is not. The sound is more lush with that electrostatic type of speed and treble clarity, however, it doesn't seem to have the same excitement and extension that my HD600 has (I know, that is actually shocking). On a visceral level, I found myself sinking a bit deeper and engrossed a bit more in the sound of the HEV as I found I wasn't analyzing it the way I do with the L3000. The 600's are a little harsher with more prominant sibilance which works for and against it at times. I think the HEV70 lacks balls though, and it comes across as merely a pleasant driver.
By the way, I use an Esoteric DV50s for as my source, and all cardas golden reference cables (except on the 600, where I think it is a cross).