Minnow Noise

[Kinski]

Built the minnow and it sounds wonderful. Strangely, when bypassed, a whole lot of white noise and an ever so faint whistle sound came though. But again, ONLY in bypass, not when engaged. Weird. Anyway, I solved most it by using insulated wire on the output. But still too much noise for me. Traced it to IC2 being hyper sensitive to its surroundings. So I built a little metal cap around IC2 that is also grounded. And now it’s dead silent. And before I did all of this, I swapped the IC for another one and no improvement was found.

Anyway, just mentioning this here in case anyone else runs into this problem.

 

[DGWVI]

Could you post a pic?

 

[Kinski]

I can post a pic a little later. But I’m assuming you want to see the metal cap? I basically made a cube out of cardboard that wraps around all of IC2. I then wrapped the outside of the cube in a few layers of aluminum foil. Then covered the outside foil in a layer of tape to isolate the metal from touching anything nearby. I then drilled a small hole through the cube and fed a nut and bolt through and used that to connect a ground wire to the cube. Attached cube to board with some hot glue.

 

[Kinski]

A bit ridiculous, but it works! It’s absolutely silent now!

 

[Cucurbitam0schata]

That is one wild solution! Nice work, thanks for sharing. This pedal is on my to-do list!

 

[Kinski]

Yeah, it’s pretty ridiculous, but works. My setup is super quiet, so I can always hear when a new pedal inserts any unwanted noise. With that IC being so close to the output jack, there was no other way I could think to isolate it.

It’s an incredible sounding circuit! Definitely my fave envelope filter ever. And the S&H is very cool.

 

[Diynot]

Thanks for posting this, I was just about to ask for a solution to my microphonic minnow problem!

 

[Kinski]

Oh nice! Let me know if this helps and what you end up doing!

 

[andare]

Just finished building the Minnow and on bypass I have the same whistle and a ticking sound when the S/H mode is engaged.
I'll definitely build a shield for IC2. I'm going to cover it with adhesive copper tape, the kind I use to shield guitar cavities, solder a ground wire to it and then cover it in electrical tape. Don't have a glue gun though.

The other problem is a significant volume drop off, especially in S/H mode. I have the trimpots to a satisfying setting but I'll have to play around with the knobs. Not an easy pedal to dial in!

 

[Stickman393]

Just finished building the Minnow and on bypass I have the same whistle and a ticking sound when the S/H mode is engaged.
I'll definitely build a shield for IC2. I'm going to cover it with adhesive copper tape, the kind I use to shield guitar cavities, solder a ground wire to it and then cover it in electrical tape. Don't have a glue gun though.

I built the minnow and experienced the same thing...

My suggestion would be to use a miniture shielded coax cable for the input and output from the pedal: land the shield for the input on the input ring, and land the shield for the output on the output ring.

Something else that can help is to use the minnow after a buffer: a low impedance signal will be less susceptible to interference than a high impedance signal.

Another option...would be to re-house the pedal with the input and output jacks on the sides, toward the footswitch, thus minimizing the input/output connection's length, and keeping the leads away from the circuit board.

 

[andare]

I built the minnow and experienced the same thing...

My suggestion would be to use a miniture shielded coax cable for the input and output from the pedal: land the shield for the input on the input ring, and land the shield for the output on the output ring.

Something else that can help is to use the minnow after a buffer: a low impedance signal will be less susceptible to interference than a high impedance signal.

Another option...would be to re-house the pedal with the input and output jacks on the sides, toward the footswitch, thus minimizing the input/output connection's length, and keeping the leads away from the circuit board.

Having side jacks is actually my preferred layout. I don't like top jacks and I'd rather have a roomier enclosure. Not an option for this pedal though.

Anyway the shield for IC2 worked and now the pedal is totally quiet on bypass. There are other issues so I posted my build in the Troubleshooting section.