Serendipity Low Gain !! Help!

[lcaseroa]

i just finished my second serendipity pedal and like the first, it dind sound like a zendrive
it have low gain
ive checked the pcb too much times and all is correct
ive used 4558 ic
if i take off the ic the effect dont sound (obviously) but if a take off both transistors the effect still sound !!!
i suppose that the problem of the gain are related to the transistors issues so i hope anyone can help me
i dont want to re build the effect for  3rd time
thanks!

[oldhousescott]

Make sure R3 is 1K and not 1M or something else. Measure it with your DMM to be sure. Same with R2, it should measure 470K (or close).

Can you post some hi-res, in-focus pictures to help us troubleshoot?

[mgwhit]

i just finished my second serendipity pedal and like the first, it dind sound like a zendrive
it have low gain
ive checked the pcb too much times and all is correct
ive used 4558 ic
if i take off the ic the effect dont sound (obviously) but if a take off both transistors the effect still sound !!!
i suppose that the problem of the gain are related to the transistors issues so i hope anyone can help me
i dont want to re build the effect for  3rd time
thanks!

When you say "low gain", do you mean "low volume" or "low distortion"?  And are you saying that the sound is the same with or without the transistors in place?

The MOSFET transistors are used in place of clipping diodes, and if they are removed you will get no signal clipping.  This should result in a louder, but cleaner tone.  Because the MOSFETs are in series with diodes, if you have the MOSFETs backwards (and the diodes correctly oriented), it should sound the same as if they were removed (i.e. no clipping/distortion).  Did you use 2n7000's?

Of course, it could be that your diodes are backwards and your MOSFETs are correctly-oriented, but you see where I am going with this.

And, yes, pics please.

[lcaseroa]

Solved!
after mesaure R1 and R2 ( they are ok) y saw a little drop of solder between 2 legs of the drive pot
now it has a great gain
thanks anyway!!

[oldhousescott]

Glad you got it sorted, and thanks for the update!