Damsel...Im not sure what 6sn7 tubes have to do with your Jadis pre(focus guys !)I strongly suggest Mullard 7025 in place of the 12ax7(late 1950s/early 1960s issue)..Higher gain,less strain but still warmth..IMO,Forget that RCA 5751 someone suggested,will take the Jadis to a lower performance level .. No point in doing that..Install Mullard 12au7s (again from the late 50s or 60s,go to ebay and buy from solid seller only,make sure to check their output before installing)..If you want a more sterile less Jadis sound try the Tele tubes...oh did you see the knobs on sale for 100 each,a deal these days..
Damsel in Distress with Jadis DPL
Caught the tube rolling bug and acquired a pair of 12AU7 "supposedly" NOS Phillip Mullard collaboration tube along with a RCA 12AX7 for my Jadis DPL preamp. Experienced a loud crack from left channel through my loud speaker. Left speaker went completely dead. Removed all 3 tubes and re-installed original compliment. Everything is back to normal. Or so it seems. What happened? Did I do any damage? Any comments welcome ~ Deb