general tech question: making pedals quieter?

[midwayfair]

What are some tips for getting a pedal quieter?

I know "twist offboard wiring" is a common one (though I don't quite understand why it would help, since all that wire is inside a metal box). Do isolated jacks help? What am I trying to isolate in the circuit?

Since the pedals are already in a big metal box, I don't think adding shielding will help. I've got my guitars pretty much dead quiet and I'd like to get pedals about the same.

[gtr2]

What particular circuits are you talking about?   Any overdrive/distortion pedal is going to increase any noise levels even if they are not completely audible before the pedal.

Josh

[rjkanejr]

I'd be curious to know what the pedal godz here have to say about this too.  I have built the Glitterratti, and the GGG ITS8 and both were very noisy for me until I got a better power supply.  I recently picked up a Boss SD-1 (Super Overdrive) because I liked the way it has sounded at GC.  Put it on my pedalboard and it is noisy as all get out, even with the NS-2 on.  I've read about that particular pedal being noisy but holy utility belt batman!  Now if I keep the drive at 5 or below, no problem.  As soon as I turn up the drive to get more grit and sustain, Oh the noise noise noise noise!  So I have learned to kick it on and play and kick it off or I just use it a solo boost.

Does it help to shield?

[jkokura]

Part of the problem is in the quality of parts, and the other part of the problem is simply the nature of gain.

Whenever you amplify something, you amplify all of it. That means, the more stages of amplification the louder the noise will be. So if you have noisy pickups, noisy cables, noisy pedals and a noisy amp - when all of them on it will be very noisy.

So, long story short - you've got noise somewhere and every amplification stage makes it worse. But the real question you're asking is how to lose it.

1. Get noiseless pickups. Humbuckers, stacked single coils, etc.
2. Shield your guitar if you're picking up radio or getting noise because of that (rare)
3. Better shielded guitar cables, shorter runs of cable, better ends on your cables.
4. Use low noise componants in your pedals like Metal film caps and resistors. Use fewer gain stages.
5. Consider adding a noise gate to your pedalboard
6. Have you amp checked for crapped out capacitors if it's more than 20 years old. Or, if it's a solid state amp and it's cheap consider saving up for a better quality, low noise amp.

That's all I can come up with off the top of my head. There's no one bullet solution here, but any one or combo of these could help.

Jacob

[shawnee]

The problem is not always outside noise and interefence (that hopefully does get blocked by a metal housing), it's noise coming from the circuit itself. Like jkokura said, quality components make a huge difference. Good 1% metal film resistors, WIMA box or panasonic film caps, and audio grade electrolytics are why a clone of a Boss pedal is so much quieter. Boss parts are just cheap.

I can't give you great detail but PCB's are designed to keep certain parts of the circuit isolated from other parts to prevent noise (maybe gain stages away from power supply components or input from output stages). If you have wiring from those isolated parts too close together, you will get noise. Long wires are like antennas for stray noise as well. Here are a few general rules that I try to follow:

1. Keep wires going to pots as short as possible without being rediculously hard to assemble.
2. Keep input and output wires as far away from each other as you can. (keep those two wires away from other wires, pots, ect. Don't let those wires lay on the PCB).
3. I use shielded wire for input and output on high gain circuits like the Chunk Chunk, Boneyard, Fuzzes, ect. (only ground one end of a shielded wire).


Buffers tame noise as well. When I am testing circuits that are all spread out (and super noisy) I usually run a Klon clone in front of it to keep the buzz down.

[midwayfair]

Thanks for the help, guys. I took shawnee's advice and separated the input and output wires as much as I could (taped them to the enclosure) and it seemed to help.

The circuit I was having trouble with was a Red Llama. It's a little quieter now, probably the best I'm going to get with a gain circuit. I would shorten the pot wires, but the volume pot's is designed to be wired directly to the switch in that design, so I really don't think I'll get much mileage out of resoldering it.

I use 1% metal film resistors, film caps, and box caps in place of electrolytic caps when I can.