6DJ8 vs. 6922?

One great thing about tubes is you can use them to fine tune your system. If your phono cartridge is a tad bright, use softer sounding tubes. And visa versa. A tube pre-amp doesn’t have a fixed sound, it’s sound is changed by the tubes installed in it.

Speaking of phono tubes: has anyone tried 5751's in place of the 12AX7's in a Herron phono amp? I gotta give Keith a call, see what he thinks of the idea. The 5751 gives up gain to the 12AX7, but that works for me.

Fantastic sources of information, thanks @jjss49 (and everyone else).

@tomcy6: Yep, my copy is on its way, will be here next week!

Wow.....ask, and ye shall receive. ;-) Thanks again, one and all.

@oddiofyl: Roger Modjeski talked about the virtues of the 6922/6DJ8 for audio use----specifically in regards to phono pickup applications, and it’s advantages over the 12AX7 (see the clio09 post above). And Tim de Paravicini, another "pretty fair" hi-fi designer (EAR-Yoshino, Luxman, Quad, Musical Fidelity) used the higher voltage 7DJ8 in his pre-amps (I own an EAR 868L).

The quietest phono/line pre-amp I’ve owned was a Dynaco PAS 2 as "modified" (redesigned, actually) by Frank Van Alstine, who used 5751’s in place of the stock 12AX7’s (cranked to full output there was only a hint of tube rush, no hum what-so-ever). So it will be interesting to see how the RM-5 compares in terms of noise. Low noise was a high priority for Modjeski. My pickups are very high output (5mV’s!), so don’t require much gain---another way to achieve low noise. The gain of the phono stage of the RM-5 is only 36dB, plenty for a 5mV signal.

Thanks a lot everyone. Lots of great info, and links to sources of even more. I have a box full of the small signal tubes I bought back in the 90’s, gotta look through it again. I know I have some 7308’s (Gold Aero iirc), 6922 Amperex’s I believe, and definitely some RAM’s.

The Music Reference RM-5 Mk.IV I just received (according to the serial number one of the last twenty of the 1,000 RM-5’s Roger made. Bone stock, no mods) is fitted with a 6922 Mullard in socket V3 (line stage), a pair of Sovtek (isn’t that the 6922 ARC uses?) in the phono stage.

I have a bassist/guitarist pal who has some old Telefunken’s, but he’s not interested in selling any. Selfish sob!

Great info, thanks one and all.