Constant noisy tubes maybe go solid state?

decooney raises an important point

with covid, many manufacturers are not manning the land lines into their offices as most if not all staff work remotely

for example, one person in another thread complains that audio research doesn't answer the phone - but i email greg c (arc service manager) and he answers me in 2 hours

@decooney  2 emails and 2 voicemail. 
It’s fine. Things are running and I’ll be moving on the QS next year anyway. 

Not to hi-jack the thread but it seems on topic - anyone have clues about the hiss on my Rogue Sphinx?

@gochurchgo the whine is less and less frequent so I want to believe it’s part of Brent Jessee’s burn-in theory. 

The hiss is a different story, steady and present all the time. I can’t listen to quiet, ambient music because it’s covered in white noise. If I turn up the amp the music covers it, but it’s very noticeable at low volumes. It’s not affected by the volume level - the hiss doesn’t increase if I turn up the volume with nothing playing. Is this the tubes or something else you think?

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. 

@gochurchgo

decooney 2 emails and 2 voicemail.
It’s fine. Things are running and I’ll be moving on the QS next year anyway.

Hmm. I did notice QS changed their contact page some. No more fill-in page. Shows email address only. He did respond back quickly though.

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re: old tubes - I do know people try different quality grade tubes in his preamps and the stock JJs he provides work well 99% of the time, functionally. Sure, others sound better and yet some old tubes from eBay and others with no reputable curve tracer or proven reputation and good results are a crapshoot. Can’t fake it on old tubes, as we all know too well. Best to buy from reputable tube resellers with real guarantees.

A friend had issues with his QS preamp as soon as he started "saving money", "getting a better deal" buying sh*t tubes off eBay. He's got good tubes now, all quiet again on the western front with his QS preamplifier. 

Selling it? If you decide to put that QS preamp up for sale, be sure to post it on Agon, someone here will grab it and make good use of it! Best of luck.