shin-ei fuzz wah noise

[Bonke]

Hi all!
I don´t know if this is the right forum but I hope you can help me.
I have got one of these pedals on my bench. It has a pretty loud hiss when fuzz is engaged. I am not familiar with this pedal but according to the client it did not use to have this noise.
I have changed all c945 transistors, all electrolyts and some of the resistors. No change in noise level.

Anyone has some experience with this or similar circuit?



Henrik

[duck_arse]

bonke, hello and welcome to the forum.

I don't know if it will help or not, but seeing as the fuzz section in yours is the same/similar to the superfuzz, have a look see in this thread, on a same/similar problem.

http://www.diystompboxes.com/smfforum/index.php?topic=112621.0

(does your unit have external power jack? if yes/then has client recently switched power source/plug pack/wall wart?)

[Bonke]

Hi!
Thank you for the answer! The pedal is powered from a battery so it is not the PS.
I will check out the other thread. Thanks!
Henrik

[pinkjimiphoton]

hi henrik, welcome to the forum
it may be also cuz you replaced old parts with modern ones, if that's what you did... so now it sounds brand new instead of old. you may find just adding a smallish cap from the volume control input to ground to tame the shizzzzzzle a little.. maybe 100-470p range. that should tame it back about 10-20 years or so, hopefully. good luck man!

i rebuilt mine too, used new transistors, all new caps and had a similar issue. it sounds new, but MAN it can tear your head off. the cap trick might help.

[Bonke]

Thanks! I will try that!
Henrik