I just spent a good 3 hours with my AKG K-401's powered by the ASL MG Head-OTL. Bottom line....I liked them better than the 701's.
Normally I use the 401's with my portable rig. I don't know why it took me so long to A/B against the 701's in the main system. I guess I just assumed they wouldn't stack up. But the bass was more present and a lot tighter, great midrange, and less sibilant highs. AND (this is a big and) the soundstage was just as big!
Maybe what I should take away from this revelation is that the ASL is just not a good match for the 701's and I really need to find a better match. Then that will free up the ASL for bedside listening instead of the portable AMB Mini^3. Haha, now I have a plan.
BTW- I know that any of the AKG's will not work in OTL mode, I only use them in transformer mode. I save the OTL setting for my Beyer's