Ok...i've had some revelations.
for one thing, and this has been observed allready by some people.
the 660 only runs on 2 batteries...thus it is taking a 3v feed (.08amp current) on the inside battery compartment. this means that you can hot swap cells while the deck is running.
pretty cool
even cooler though, it will run, er..better said, it seems to run... w/a 6v DC feed externaly. Marantz does not recomend, advise or endorse it, but a tech told me that it "should work".
I just took a chance and hooked up a 6v 5amp SLA to mine and it powered right up. Now i'm going to hook up my hungry LSD2 mic and power it up and see that everything is fine and running for a long time.