Fuck my 5150, fuck my mesa, fuck it all.

TBH 5150's can put my teeth on edge but sometimes they can sound better than Mesa's just depends on all the other variables .
Never found my holy grail with Mesa Peavey or Marshall tho.
 
Fuck my 5150 too man! Fired it up yesterday and for some reason, suddenly it sounds like someone hooked a fuzz pedal up to it. Sounds like a blown speaker, but all of the speakers sound exactly the same. All the crunchy goodness is just gone. Now it just sounds like a gay clown gargling cat piss. WTF!? Also it was like the presence kept coming and going, like someone was moving the knob from 0 to 10 back and fourth. Any ideas?
 
No, 5150's do not inherently sound like that, listen to this:

http://www.ultimatemetal.com/forum/rate-my-mix-tone-threads/646266-some-brand-new-label-work.html

And Ryan has gotten plenty of fizzless 5150 tones on that level (eg the King Conquer reamps he did for the Sonic Assault studios boys) and I think is more than capable of diagnosing problems in amp settings/mic position/boost choice etc., which leads me to believe that a) the amp is indeed fucked up, or b) he's just trolling the fuck out of you guys.
 
Thats not what I meant. I was just stating that there is a level of fizz that can never be tamed by reducing the highs and the presence. The only way to make it go away is getting the amp up to a decent volume and using the highs as the source of upper mids and keeping the presence down, followed by the standard low pass in post processing. Unlike other amps like say rectifiers where by reducing the presence and highs can completely attenuate those frequencies.

Fizzless tones can be had, it just takes the right mic position, right settings and proper volume. But from what ryan posted, something somewhere is extremely wrong or he is indeed trolling.
 
With the new output tubes the grid bias could be set at a shitty spot. Put the meter on it and crank the volume until you find the sweet spot.

Maybe it is just filter caps going bad. Check for leaks or bulges. Some people have trouble with ghost noting from modern day electrolytic caps just being shit from the get go..

?? just sum guesses.