Greetings! Im currently parts swapping through 10 or so pairs of hd-280's, mostly with one dead driver, trying to assemble as many working pairs as possible. My customer says he doesnt want to spend $30 each for factory replacement drivers, so Im looking into some more affordable offerings, just...

I just picked up a really clean and fully functional Sha Gold (non reference/ maestro version), which appears to be stock from what I can tell. It's got some sovtek 6922's in it which sound ok, but definitely leave some room for improvement. The only other tubes I happen to have on hand that are...