2. amps-preamps
  3. 161387-96791

Constant noisy tubes maybe go solid state?

I have a Quicksilver Line Stage Preamp (12AT7) mated to an Odyssey Khartago Stereo. Overall I like it. Way too much gain but I digress. Weeks after receiving it I rolled in a few different tubes, kinda fun to color the sound signature. I liked rhe RXA black plates I got and those stuck around for more than a year. They started going microphonic and making noises so I ordered another pair (noisy) then another different vendor (blasts of white noise) and another set that arrived today (one is noisy as holy hell and one seems fine).

So where does one order preamp quality tunes that are quiet? Is there something I’m not requesting when ordering? Maybe dump
snd go solid state? I’m trying to be humorous because I’m pissed. Ha.
gochurchgo
leemaze
330 posts
 
Oh boy - what a bummer!  Did the replacement RCA from Brent sound good?  Let us know if Upscale takes those back?
axeis1
291 posts
 
To the OP: The Best tube vendor is Andy Bowman at Vintage Tube Services. He’s been at this for 30years! He’s as honest as the day is long. 
gochurchgo OP
920 posts
 
Went and threw on the 12db attenuators I had and now everything is dead silent. All the tube noise I have been getting (which didn’t get louder with the volume pot) now gone below the threshold of the attenuators. I’m pondering snagging a 6db pair just to see what that does.

So by this, if I theoretically could lower the gain of the QS to say <8 FB gain then I should have no issues. Right? Or is it non linear and I’m over simplifying?
alchemyman
21 posts
 
Get some ECC83 JJ gold pins. Very reliable -- not expensive.  Mullard NOS are not bad, RCA clear tops. Tesla 803c in place of 12AX7 are nice, but hit or miss as to what you can find.

Try here:
https://www.amplifiedparts.com/tech-articles/12ax7-comparison-current-made-tubes
jackd
1,068 posts
 
@gochurchgo 

If the 10db attenuators work and don't effect the sound to your ears I wouldn't waste anymore money on attenuators.  If you haven't tried the 12AU7 tubes yet that might be a better avenue.  Also my personal opinion but if you want to continue to deal in NOS tubes without getting duds I would stick with Andy at Vintage Tube Services. There are still a couple of reliable dealers on Ebay that fully test and back their tubes but they are few and far between. 
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