Author Topic: ...and at that point I was sure I needed some help.  (Read 3624 times)


...and at that point I was sure I needed some help.
« on: November 16, 2004, 12:37:57 PM »
hi guys,

been lurking on here for a while, and now I'm after a bit of advice:

I've built the NPN boost (and jolly good it is too) and been fidling with a few other things, based on what I have been reading on here.

My problem is that I'm getting a weird sort of fuzz/distortion noise when I play bass notes (think an open E5 power chord).

It gets worse the more the gain is turned up - below half it's not too bad - on full gain it's really breaking up badly.

It's also worse the harder I hit the strings, and higher up the fretboard it's not so bad (or maybe It's more difficult to hear)

it's not a musical sort of breakup. I can hear the transitor gaining up and how it's meant to sound.

The breakup is below it, it's the same sort of sound you get when a speaker is on the way out and it can't handle the low freq's. Not nice!

I built a new one last night and they both suffer from the same symptoms. I have tried 3 differant amps and 2 guitars and it's still the same sort of breakdown of signal on the bass.

I've even changed the transistors (Germ 2222 and Si 547 and a few others) and the problem is still there. :cry:

Sometime it seems worse and sometimes it seems not so bad, but I guess that might just be me.

any help would be great - I'm running out of options,



Hey there.
« Reply #1 on: November 16, 2004, 01:15:50 PM »
I'm no expert by any means, i'm still learning also, but i have seen your problem a couple of times, and it has been a very elementary answer.  Is it your cable?  I have seen that as the problem a couple of times.  If that isn't right try checking your solder joints.  I know that has also been the cause of many problems, also make sure nothing is crossing or shorting out, and you may want to try a different pot, sometimes pots are bad, i would doubt that if it were new though.  Those are all the answers i can offer up, but you my want to wait until an expert gives you an answer.
Hi Paul.  Welcome.  We are all Stompboxaholics

I am so cool.


...and at that point I was sure I needed some help.
« Reply #2 on: November 16, 2004, 01:44:53 PM »

thanks for you reply. - I've just tried a differant lead and it's still the same  :?

I'm going to make another one tonight and see how that works out.

In my limited knowledge I'm going to guess that something is getting overloaded in the curcuit.

But it's strange that it's the same sort of problem in the 2 differant curcuits I have built (the NPN boost and a fuzz).

anyone else with any ideas...?



...and at that point I was sure I needed some help.
« Reply #3 on: January 18, 2005, 07:57:08 PM »
I'm from Portugal so sorry for my english...
I'm also no expert  but it seems that you are having problems with the lower guitar notes, right?
I use to have that problem till i find out it  that it is dued to too many low end gain getting distorted (it seems that  too many low and distortion don't get along well). I tried several  things like a small value capacitor before the distorion or other kind of hi pass filter within the distorition and it helped alot.
Give it a try and than let me know if it worked.


...and at that point I was sure I needed some help.
« Reply #4 on: January 19, 2005, 09:46:17 AM »
I think rangerman is on the right track.

If the signal is futzing out on bass notes, I would suspect a capicitor.  Perhaps, if you soldered it, it got too hot.  Or it could just be a dud.  The fact that the bass notes are not getting through well enough suggests that you should use a larger value to let those lower freqs in.

Hope that helps.