I have an ASL MG HeadDT headphone amp. I had picked up 2 Sylvania 5751 tubes to replace the center ECC83. When I replace the ECC83 with either 5751, I get a very loud buzz in the right channel. I've heard of other users using 5751s in their ASL. Did I buy 2 bad tubes or is there something I'm missing?
Tubes - Sylvania 12ax7 vs 5751 3 mica blackplates
I am new to tubes and am wondering, "Are NOS Sylvania 12ax7 triple mica black plate tubes identical in every way to the famed Sylvania Gold Brand 5751 triple mica black plates?" One source claims that if the 12ax7's have the same gain, THEY ARE 5751's even though the boxes and labelling on the tubes say 12ax7. Can anyone confirm or comment on this? Is it possible that Sylvania "mislabelled" tubes? I am curious if there are differences in the construction, quality, value (cost) and most importantly sound.