This is a tricky one, I bought a 5150 a little over a 2 months ago. Its great , the clean channel is fab and I really like it. Except now it has a bit of hiss. I've changed cables , taken everything out of the loop, gone straight in, turned it on and not connected anything and it has a low volume hiss.
The only change since I bought it is I've had some frequency specific hearing aids fitted (they boost all frequencies but the curve is pushed to boost everything from 1k upwards as thats where my hearing is severely lacking (along with tinitus). Has anybody else got one of these amps and has better hearing than me ? Does yours hiss? Should mine?
I expect it to be a bit noisy on channel 2 as its super filthy dirty, but its a bit disconcerting on the clean channel. Im in work at the moment but when I get home I'm gonna to check a few more things out, try it without my hearing aids and with again but its been doing it for about a fortnight ( just after I had the aids)
TL:DR my amp hisses is it me?
Comments
Its a shame I can't leave the buggers in though as they oddly keep the tinnitus under control, ah well you can't have everything (or sometimes anything)
Your hiss on the clean channel may be due to a lot of different things, besides the fact that these amps are known for hissing
Could be hissy pre-amp valve - easy checked by swapping out or around the valves.
Could be a mute relay not working
a failing plate resistor
etc etc
V1 (clean channel) is usually a JJ or TAD ECC83 chosen for its low noise floor
V2 (dirt) is a PS Vane ECC83 that can be a touch noisy in the clean position in these amps but is fine for da gainz
Sounds funny, I know... but I've had that from a horse's mouth. Can say no more. ;-)
They aren't overtly noisy (hiss) for a high gain amp, but equally they are far from silent.
If you’ve got another good quality ECC83, you could pop it in V1 to see if that improves things.