Constant noisy tubes maybe go solid state?

You should clean out your tube sockets, it may have some residue in there.

@yogiboy the purpose of the thread was bad tubes. Gain is a design issue. For now good tubes are the answer until I can search more into other varieties.

@gochurchgo

an obvious point perhaps

but if your tube preamp has too much gain for your power amp then slightly noisy tubes in the pre get highlighted moreso than if the gain match were more appropriate, right?

so the issues are inter related which is why we have been talking about both - ’’component synergy is the lifeblood of a truly well performing system’’

06-06-2018 5:23pm by Jackd
...As the Odyssey amps have low input sensitivities in the 1 volt range you need to be careful of tube preamps with high gain especially if your speakers have sensitivity ratings much over the mid-80's range.

Was member jackd on to something a few years ago, about pairing higher gain preamps with the Odyssey Khartago amp, 9th post down?

https://forum.audiogon.com/discussions/preamp-suggestions-for-hot-rodded-odyssey-khartago

@decooney 

And it's still true over two years later.

@gochurchgo 

Until you can resolve in your mind what to do going forward about your gain mismatch once you get a pair of clean tubes then there are two relatively inexpensive things you can try between the Quicksilver and the Khartago that will help resolve your problem.  Number one is an inexpensive passive like the Schitt Sys and the other a set of passive attenuators.  Neither one will "greatly effect" the sound you are getting and both will buy you some time while letting you enjoy what you have now.  I have used the Rothwell attenuators from the UK with many different gear combo's and never found any "dramatic" effect on the sound but there are also less expensive versions from the Pro Audio world available at places like Guitar Center and Sweetwater. I have used Odyssey amps since 1999 with a number of tube preamps based on 12AU7, 6DJ8 and 6SN7 tubes and the issue was always the same if there was a gain mismatch between the preamp and the particular Odyssey amp and the speaker sensitivity got close to or over 90 db.  Just  how it is.