Too low or too high voltage? I need help!

[SlyStrat]

What would cause this: my Marshall 2204 preamp distortion sounds like buzzing bees, and I had to back way off on the preamp volume compared to last week. The distortion is making the notes all mashed together. Sounds like a REAL CHEAP fuzz pedal. And I have to turn the master up more to thicken the tone.
Would this be low voltage or too high? How would either problem change the bias? Does this seem too hot, or too cold?
Then I tryed the '77 NMV. NO distortion until I had it on 10! Then all mushy sounding. It normally has nice breakup starting at 6. That amp is WAY too clean and lifeless now.
And all amps sound thin, unmusical, a nasty trebly buzz on top of each note.
Just a week ago, my tone was great. It inspired me to play longer.
It seems like when it rained last week, the tone started getting bad. Then it got colder and snowed the last couple days. The tone got worse.
Theres a ton of wires on the poles behind my house, with a crap load of splices. I live in the city with thousands of houses jammed together. All built back in the '40s.
I can't enjoy something we all love to do: play guitar.
I'm gonna shoot myself.

[John Phillips]

If it's a voltage problem at all, it sounds like too high rather than too low. It would have to be really extreme to make that much difference though - especially raising the breakup point from 6 to 10. I've never heard anything remotely like that just from supply voltage changes... although I'm in the UK, where the regulation is a lot tighter.

Usually higher voltage will give you a cleaner, brighter tone, probably colder bias (though it depends on what part of the operating range the tube was biased in before), and buzzier distortion.

If you think it might be the cause, buy a cheap digital multimeter - a $20 Radio Shack one will do fine, they're handy for all sorts of other things too - and measure the voltage on days when it sounds good and when it sounds bad. If there's a big difference, you may need a voltage regulator or a Variac.

[walterw]

not to be cheeky, but two old marshalls going south at the same time? i would suspect something entirely different, and simpler, in the signal chain, like a bad cable or a dying battery.

[trisonic]

Few weeks back I was getting 146 volts at the outlets.
Called power company who came out and said it was my problem get an electrician to check neutral circuit - then I found out neighbour had the same problem (one of the symptoms is erratic lights) she rang the power company (as did some others) and it was a neutral fault on the next block over. Power company's fault, of course.

Best, Pete.

[John Phillips]

Ouch... that's really very dangerous, even discounting any tonal effects. A voltage rise that bad most definitely would affect the sound of the amp, but more importantly it would put many of the internal voltages over the safe rating of the components. 146/120 is 22% high, which would make the B+ in an amp designed for 450V rise to almost 550V. Many filter caps are rated at 500V, and some tube types really wouldn't like that either.

Given the fire hazard with other domestic appliances too, you'd think that the substation would have a trip to stop that sort of thing happening...

[SlyStrat]

I have changed amps, cables, everything. My amps sound fine at my friends house. I have something weird going on at MY house. I have checked the voltage, and that doesn't seem to be the problem.

[walterw]

wow, that's a corker.

cabinet? speaker cable?