Okay its been a while since this thread got updates, but I thought it was worth a mention.
Just attended a little meet between friends and the MA900 was the surprise star of the night. I had a chance to compare the MA900 against the HD650 and we were all somewhat surprised to find that the MA900 actually sounded quite similar to the Sennys. They had essentially the same character, with the biggest difference being a more forward mid section on the MA900. On some tracks the HD650 sounded better with richer vocals, on some tracks the MA900 seemed clearer and the HD650 congested. Overall though the MA900 just sounded like a HD650 with less of a veil. (I happen to love the HD650 as well).
Everyone was pretty impressed especially given the current Amazon Japan pricing of about $170 USD. This is coming from a HD650 owner, a Shure 840 owner and a HE-6 owner. (Obviously it wasn't better than the HE-6, he was just impressed for the price.)
I have a loaner pair of modded HD580's which I'll do some comparison with, and then update my MA900 / AD900X review thread.
Hope this helps anyone interested in the MA900. I swear the MA900 deserves way more love than it currently gets.
You might want to fix the MA900/AD900X review link... though I did enjoy reading your earphone review.
Anyway, I got a MA900 to play with at the moment. One thing I want to ask to people who own the MA900, is it just me or are these headphones much harder to drive than their specs would imply? The MA900 seems significantly quieter than my other headphones (closed HD669, semi-open MDR-XD200, open ATH-AD900) at the same player volume level. I had expected them to be the other way around given its high sensitivity and ludicrously low impedance. Is this normal or is there something wrong with the one I have?