While the stock MC275 IV is one hell of a musical amp with it's stock tubes, one can significantly increase the amps resolution and musical attributes by replacing all of the stock tubes to begin with. I swapped in quad matched Genalex KT88's and NOS Mullard CV4004's and CV4024's and the stock tubes sound lethargic and confused/diffused by comparison. Also of interest is that if one uses the SE inputs that installing Cardas XLR caps on the unused XLR inputs increases resolution and image solidity. I imagine the reverse would be true if one were using the XLR inputs as well.
Of course, a really well engineered amp stand and upgrading the power cord also go along way to wringing out all this musically complete/superb amp has to offer. Don't forget the fuses as well :-)
Of course, a really well engineered amp stand and upgrading the power cord also go along way to wringing out all this musically complete/superb amp has to offer. Don't forget the fuses as well :-)