I've been playing guitar for a few solid years of heavy practice and such, but I can't figure something out. Either my amplifier needs fixing (or just to buy a new amp) or my guitars (all 4 of them) are giving some odd sounds.
When playing and sustaining a note (well, playing at all yields the same results, but sustaining any note is the best way to pick it out) I hear this weird and very inconsistant feedback. It's almost like a wavering sound (not like the kind of sound when you're out of tune). There's no crackling to be heard (it's a clean sound definitely), but basically the best way I can describe it is an inconsistant wavering sound that comes and goes at different times. Imagine watching TV but you've got this ever so thin filter over the top of it. You can't notice it during most of your viewing time, but every now and then you notice a small out of place thing. When doing some solid chord progressions you don't hear it at all (but that could be because I'm just not sustaining anything for any significant amount of time). When doing a solo (like, earlier I did the solo for Cherub Rock) is when I hear it most. The first note is a bend/sustained note on a high fret (I believe the 15th on the B string) and that's where I tend to hear it the most (on high notes).
I'm trying to figure out if it's something I can easily fix or if it's more likely all 4 of my guitars (no idea how that would make any sense).
Posts
If it's what I think it is, it could also be the strings above the nut. Try putting a bandana or something around it. To deaden them. This sounds retarded I know, but many acoustic players do this.
Are we talking about an electric guitar?
possiblities:
60 cycle hum
bad tubes
bad ground
ground loop
bad cables
intonation is off and throwing odd harmonics on higher frets
it's a solid state amp, Line 6 Spider 3 (I need to get a better amp soon anyways. Need to get a half or full stack).
I play double bass, and double basses typically have huge problems with feedback when amplified, because the bass tone hits the body which is a huge box created to emphasize bass frequencies.
But the wavering I have more experience with because I just started playing mandolin, which has string pairs (like a classical guitar, for those unfamiliar with mandolin). The courses need to be tuned exactly the same, though, because if one of the strings is slightly out of tune, it will cause this "beating" sound which happens because the waveforms are knocking into each other.
One of the tones you're hearing could be a simple byproduct of your amp. But the fact that it sounds like it's beating makes me think something else in your room is resonating, causing the feedback you're hearing. Especially since it's happening across all of your (assuming they're different) guitars. If you had hollow-body guitars or acoustic guitars with pickups installed, and it only happened on those, it would be more obvious (you'd probably have figured it out already, in other words).