BHKPre not working with 6DJ8’s?

[brett66]

Anyone having issues with a noisy channel on the BHK preamp

Eh, it’ll work but I hesitate to recommend using them. We regularly get calls and emails from folks mentioning their BHK pre is popping, hissing, etc. They mention that they have tried multiple tubes so they know it’s not a tube issue. The guys in the lab then test it and sure enough, it fails AP. Check the tubes and 9/10 there will be non 12AU7 inside. That being said, absolutely roll the tubes and have fun with it. Just know that the Pre’s tolerance is only so wide and one could run into nois…

Why doesn’t the same occur with NOS 12AU7 tubes (as much as of course there are bad 12v tubes)? The 6v tubes demand more current.