I really like the Preferred Series KT88 from The Tube Store, in Canada, in my VAC 300.1a. These are identical to Shugang KT88SC, like the original stock tubes (which VAC stopped being able to source, I was told by Brent) but are far more dependable for some reason. The VAC tubes constantly had problems whereas the Preferred Series versions have been rock solid for me. The same tube is also branded Penta KT88.
I much prefer them to the GLs, which are mechanical to my ears. Too bad, because I bought two match quads plus a pair and they sit in my tube closet.
I much prefer them to the GLs, which are mechanical to my ears. Too bad, because I bought two match quads plus a pair and they sit in my tube closet.