Trouble shooting noise that’s not the PS

[ac30irons]

Hey all, how do you guys start trouble shooting a noisy pedal. I’ve worked out it’s not the PS as it does it with a battery. The noise is the same with any guitar with the volume up or down. When you play you can’t overly hear it but when not playing it’s like a sand storm. Holding the strings makes no difference.

Also a noise gate, no matter the setting does not do anything.

Should have said, it’s a G2. My P2 is near silent.

 

[BuddytheReow]

Some circuits are inherently noisy either because of the components used or the way the circuit is designed.

In your circuit try swapping out the ICs and see if that makes a difference. If that doesn't work you might try to locate where the noise occurs in the circuits. Use an audio probe and trace the circuit.

 

[JTEX]

If, apart from the noise, it seems to work/sound as expected, I would first try to compare notes with somebody else who has the same pedal, tweaked to the same gain and other settings. Make a recording (play/stop/play), have them make one, compare noise. I was asked many times over the years to "fix" things that had been that way, by design, since day 1 - until it eventually bothered somebody. Just a little insurance policy before spending hours and hours on troubleshooting.

 

[ac30irons]

Thanks dude. No ICs in this one. There are only a hand full of different components to the P2, hence my confusion.

Some circuits are inherently noisy either because of the components used or the way the circuit is designed.

In your circuit try swapping out the ICs and see if that makes a difference. If that doesn't work you might try to locate where the noise occurs in the circuits. Use an audio probe and trace the circuit.

 

[ac30irons]

If, apart from the noise, it seems to work/sound as expected, I would first try to compare notes with somebody else who has the same pedal, tweaked to the same gain and other settings. Make a recording (play/stop/play), have them make one, compare noise. I was asked many times over the years to "fix" things that had been that way, by design, since day 1 - until it eventually bothered somebody. Just a little insurance policy before spending hours and hours on troubleshooting.

Thanks dude - need to find someone with one now

 

[jwin615]

Audio probe starting at input then in and out of each gain stage. That will help point to where in the circuit the noise is coming from.

 

[Harry Klippton]

Is this one of those Cornish designs that needs a really specific spec'd diode to work correctly?

 

[ac30irons]

Audio probe starting at input then in and out of each gain stage. That will help point to where in the circuit the noise is coming from.

Done - it would seem it’s coming from the D4 and 5/Q4 region !!!

 

[ac30irons]

Is this one of those Cornish designs that needs a really specific spec'd diode to work correctly?

It was however it’s been re traced.