[quote author="buttachunk"]What the dif between MR3 and MR4 ?[/quote]
i have no idea and would also like to know.
outside of this forum though, one person who will probably know is Allan Waugh at Innovative Precision Technologies (http://www.ipt.name/), he used to work at Harrison and now services these boards. I spoke with him a while ago about pots/recapping and he was really helpful.
another one would be john klett over at Prosound web, from what i heard there was lots of useful Harrison info in the Recpit forum (which now is unfortunately unavailable.)
...and there is always www.recordingconsoles.net :wink:
j.
PS: i didn't mention GLW/Harrison, 'cause when i called them.... they seemed kinda lost and i couldn't really get any useful info out of them. (maybe all the old techs left the company...?)