Originally Posted by runeight
MHO is that device matching is not needed. The Toshiba transistors should be selected in the same hfe class though.
If I were matching I would match two things.
1. The O/P mosfets,
2. The mu of the two triode sections or even all four sections in both channels.
But if I were building the amp I would not make the effort to do this. I do understand that others have different diy preferences.
I know this post is from way back in 2009. But I'm a little curious about tube matching, even if it's not utmost necessary.
I have a local guy that sells tubes out of what I deem to be a large garage. Place is a veritable rats nest, but this guys knows where everything is. He says he has 6GM8s. Not sure what brand, etc. but he was asking what % I want them matched to. This is what he asked...
"By matched pair do you mean with matched electrical characteristics? If yes, how closely matched, in percent and which parameter(s)?"
If I chose to go this route, what should I tell him? So the mu is the only thing that should match? Would I get a weird look if I asked for this?