Driver/Input tubes


I need somebody to either explain or steer me to an explanation of the 12AX7/12AT7 tube's purpose in my Jolida JD502P power amp. I get preamp tubes in a preamp, but I've found it difficult to find a clear explanation of what the "driver" and "input" tubes are actually doing, and their relative importance to the sound of the amp. The 502P seems to have a typical compliment of these tubes, sharing its basic design with a lot of apparently similar power amps. Brain trust...hep me...hep me...
wolf_garcia
Maybe Atmasphere will see this thread and post a reply;if he does you can not get any better information in my opinion;also advice so far has been pretty good.
Back to the original question, are the 12AX7's the input tubes and the 12AT7's the driver tubes? Is it true that the input tubes have a greater impact on sound quality than the driver tubes? TIA.
Jed,
You want to get matched gain. I'd recommend balanced triodes as well, but that one is not as essential. I wouldn't worry too much about the other options. And Tom is correct that the pre-amp tubes on that Jolida are the 12AX7s and they will make the biggest difference in terms of shaping the sound. The 12AT7s are driver tubes and you shouldn't spend as much on them. Get something quiet and reliable and don't worry about their supposed sound characteristics. Spend plenty of time listening to the amp with what's in there now & decide what you want to change regarding the sound -- post that here & you'll get loads of recommendations. I have some Jolida gear as well, they're great bang for your buck amps.
Batch
My understanding is that the 12ax7s are the input tubes, have the greater influence on tone, and the 12at7s do the driving. It seems the EH 12at7s are relatively well regarded in the driver role so I'm using them (they're stock with a new JD502P), and switched the Tung Sol 12ax7s to a matched pair of Thetubestore's "preferred" ones (select Chinese it would seem) and I love 'em...they provide a little more sparkle, tonal accuracy, and aren't expensive.
I need some spare 12ax7s and 12at7s for my jolida 3502s. I have the mullard 6201 gold pins and the russian Gold Lion 12ax7s from Upscale. Are the new mullards ok? Thanks Ted