Uneven output on some strings, on some frets

[zener]

I've built a Sansamp GT2 long ago and it's working well (really heavy) aside from this thing:

I got stronger output on some strings on some fret up the neck For example, on the 2nd string, I use to have this stronger/higher and a bit fuzzy note on the 12th and 13th fret. On the 3rd string, I have the same thing somewhere from the 14th to 17th fret. On the 4th string, somewhere from th 20th to the 22th (my axe is a 24-fretter). They have the same sound characteristics. I played it by picking on one string from the 24th down just to see exactly where it occurs. The increase in output in the frets I mentioned is really audible you'll think a gain knob was suddenly turned all the way up as you moved from the "non-offending fret" to a fret I mentioned above.  

I tried the same thing from marshall, mesa and fender settings and it occured exactly where it did in other settings. And the variation of the abnormality is really proportional to the amp setting of the GT2. I was even careful 'bout my picking strength to make sure that it ain't the one causing it. The controls have nothing to do with it. When the effect is on bypass, it just like, well, bypaasses, clean and there's no abnormality.

Any idea what's causing it?

TIA

[zener]

Ok, update:

I've never noticed it before because either (1)I'm so amazed with how good it sounds as i play some fast solos and crunchy riffs (2)I set it so loud.

This time it was really quiet down here in the basement and I only used a cheap PC speaker as my amp. It has two 1/2w 8ohm speakers. I also tried my Big Muff and it only occured in the 2nd string, 13th fret and it was not that audible as that of the GT2.

I think it's not the guitar because there's no problem when I play bypassed. It seems that the guitar (or the pickups to be exact) are reacting differently on different effects. That's my wild theory.

So does anyone experienced this in your effects? What could it be?

TIA.

Zener

[bwanasonic]

If it only does it with those speakers, I'd suspect the speakers. More specifically, the speakers response to the GT2's output. I built a little mini-amp on one of those 2001 projects kits, and the little 2" speaker does the same thing when driven hard.

Kerry M

[zener]

If it only does it with those speakers, I'd suspect the speakers. More specifically, the speakers response to the GT2's output. I built a little mini-amp on one of those 2001 projects kits, and the little 2" speaker does the same thing when driven hard.

Yeah, actually, I've thought of that just a while ago. How stupid of me not to realize it early. Sorry for me that I don't have any PSU here to power my 10W amp here. I just hope that it was really those 2" PC speakers.

If indeed it's only the speakers, then how does it happen that it's only occuring in a certain fret and in some strings only. And those frets are not even the highest or the lowest in the neck (somewhere in 12th to 22nd fret on strings 2, 3 and 4). Maybe some not-so technical explanation here, anyone?  :roll:  :wink:

Thanks

[WGTP]

Try a different guitar and see what happens.  All guitars have notes that are stronger and weaker.  Most speakers are the same, unless $$$  Also rooms have peaks and nulls.

[zener]

Try a different guitar

Sorry for sailing this off the topic. The truth is, I've never hold any axe other the very cheap one I have (of course, a few just to test them when I bought this one). I don't have a band nor anybody who has one. I'm sitting here alone just me, my pc, axe, DIY effects and a homebrew amp. Sometimes, I just keep myself contented browsing through music123.com's catalouge and wishing that someday I can have just one dual humbucker, 24-fretter, floating bridge from Ibanez or Washburn.

Damn. Sometimes, you can't help but to let these kind of feelings out especially when your birthday is two weeks from now  :roll:  :wink: .

[bwanasonic]

I'm sitting here alone just me, my pc, axe, DIY effects and a homebrew amp.

Hey, if all you have is a piece of wax paper and a comb, use it! Make some music!

As an experiment in resonant frequencies, try this- Find a large can or maybe a cylindrical cardboard box (oatmeal container) , and hum or sing into it. Start with a low tone and *sweep* upwards in pitch. You will find a certain pitch(s) that suddenly gets louder. You have found the resonant frequency of that container.  

Kerry M