mc275 is auto bias, correct? if so, then you don’t NEED matched tubes, though it may still be better to have them
another piece of advice... don’t chase old stock power tubes in the 6550 kt88 type, new tubes are excellent old tubes won’t outperform them, old stocks are giant waste of money from a sound quality perspective
another piece of advice... don’t chase old stock power tubes in the 6550 kt88 type, new tubes are excellent old tubes won’t outperform them, old stocks are giant waste of money from a sound quality perspective