I replaced the resistor and carefully watched the bias, nothing noteworthy so far and it is back playing.
The tubes should have 400 hours on them. I will get a matched pair from tubestore (as that is the source for the other 6 tubes that had no quirks) ...just in case. Also on order 2 matched pairs of Shuguang 6550As to be tried out with the 20 year old ones I already have.
The tubes should have 400 hours on them. I will get a matched pair from tubestore (as that is the source for the other 6 tubes that had no quirks) ...just in case. Also on order 2 matched pairs of Shuguang 6550As to be tried out with the 20 year old ones I already have.