Well, I love my ARC REF6 and I have very little interest in paying $5K to upgrade it. I suspect that as with a lot of upgrades, the improvements might be audible, but not by much. I am sure that there is something that I can upgrade for $5K that will make a bigger difference. But hey, if you've got money to burn, an improvement is an improvement, however small it might be.
Audio Research REF 6 to REF 6SE upgrade.
UPDATE””””””””” I just got off the phone with Audio Research about the REF 6 to 6SE upgrade and I was told that the price of the upgrade went up from last year from $3500 to $5000. I was pretty shocked. Also he said that it will not have to be done by the service dept as they have a guy who strictly does Ref 6 upgrades. as all parts are in stock and it will only take 14 days turn around time.