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

Showing 4 responses by audition__audio

audition__audio
1,325 posts
 
Very few JAN (military) tubes were electronically any different than the normal tubes in the same family. They will sound the same, last the same length of time and, at best, were specially tested for certain characteristics like shock/vibration. 
audition__audio
1,325 posts
 
By wary of any tube seller that uses the term: "NOS in white boxes". Much more common with JAN tubes that were bulk packed, this term usually means that the tube tests as NOS and comes in a white box. Not the same thing. 


audition__audio
1,325 posts
 
True NOS has little to do with test results. True NOS is a tube which has never been in a circuit other than a tester, which can be hard to discern at times. Most true NOS come with original boxes. Being NOS doesnt make the tube better it just means that the tube has never been used. Tests NOS is not true NOS. "NOS in white boxes" is rare and it is a misleading and some would say dishonest claim.

Further, I have seen up to a 20 to 25% variation in the test levels of true NOS tubes from the same family and manufacturer. Add to this the fact that each tester is idiosyncratic by tube type and you quickly understand that the average NOS reading listed of a particular tube is kind of a fiction. 
audition__audio
1,325 posts
 
The problem with your Rogue is most likely not the tubes but just a higher noise floor with the component. Could be an issue with gain and also probably just the price you pay for a less expensive component. You can only do so much for a given retail price and certain short cuts are often taken by manufacturers in order to reach a target price. 
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