Shin-ei Fuzz Wah noise

[Bonke]

Hi all!
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

 

[radardoug]

The client is probably lying.

 

[JohnRoberts]

Fuzz effect involves a lot of gain...  a lot of gain means a lot of noise.

JR

 

[Bonke]

The client is probably lying.

Haha! I´ll tell him that. ;D

 

[midwayfair]

What's it being powered with? Still a battery or is there a power supply involved? Usually adapters will make a whining noise but some will make fuzzes hiss. (The Strymon one, for instance, makes pretty much any gain pedal a white noise generator.)

Otherwise I'm also going with the client is lying because you've done everything else

 

[Bonke]

It is battery powered.
Is it possible that the diodes can be the reason? I have never seen that before but... :-\
Henrik

 

[midwayfair]

Audio probe and see where it gets introduced. If it's not until after the third transistor, then it's more likely than not just the gain level.

 

[CJ]

had a noisy wah in the shop the other day,

issue was they mounted the in/out jacks over a painted surface,

sanded the contact area and the noise went away,

now we stress over a Fender Frontman 212R, what a solid state POS,  ;D

 

[Bonke]

had a noisy wah in the shop the other day,

issue was they mounted the in/out jacks over a painted surface,

sanded the contact area and the noise went away,

now we stress over a Fender Frontman 212R, what a solid state POS,  ;D

Yes I will check that out.

I definitely second your view on the Frontman. It is a relatively cheap fender cabinet with some attached stuff for your spare part shelf. ;D

Henrik

 

[Bonke]

Did scrape off some paint from the in and out. It helped a bit. Thanks for the help guys!!!
Henrik