Small Clone volume drop and distortion

Started by e_archie, February 03, 2005, 05:19:58 PM

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e_archie

I built a small clone.  The chorus works and sounds great, but it's way under unity gain and there is a faint but distinct second voicing that is very distorted.  Any ideas on what I should check?

H.Manback

If you hear "two" signals you can be reasonably sure that one of the signal paths is messed up. My guess is the "wet" path, since well, the "dry" path is just a trace :D

If you have a audio probe set up thingy try checking what is coming from that 20k resistor before the output opamp (you should recognize a mix circuit in that opamp, and the two inputs for it are the 22k and the 20k resistor)

If you can't use a probe or anything, go over all your soldering work in the "wet" path, so go over the LFO, the CD4047 MN3007 and all that stuff. If you get your original sound but way under unity gain you can be pretty sure that your input buffer and output buffer are ok (the opamp at the input and the one at the output).

But... since you say the chorus works and sounds great, it has me wondering if the input isn't shorted to the output somewhere in the wet signal path... maybe accidentally shorted something at pins 7&8 of the MN3007 (this is really wild guessing)???

triskadecaepyon

I would check your wiring; it seems it's getting mixed back in somewhere.  Another reason could be that the trimpot is not biased right.  You should check the trimpot (trimmer) and see if that does the trick.

e_archie

The problem is definitely in the buffer.  I removed the 1uf cap and 20k resistor to isolate it.  Huge volume drop and some distortion.  All the ground, 9v, and 4.5v readings check out.  Time to find the faulty component.  That sucks but at least it's just the buffer.  Guess I'll start with the 4558.

dosmun

I also noticed a Volume drop in my Small clone.  It is not drastic but there is a little drop in volume.  I also recently noticed a slight distortion to the sound.  Is this normal?

Del Pedro

Have you adjusted the trim pot? I finished my Small Clone yesterday and before adjusting the trim pot there was some slight distortion, too (but no loss of volume).

dosmun

I played with the trimmer a bit and everything seems to be OK again.