What makes an OD noisy? (NPD is it defective or just not for me?)

[Dave Locher]

I bought a used Aeon drive (Mammoth Electronics Tubescreamer kit) because it was cheap on eBay and I'm a sucker for handwired pedals. A/B'd it with my MXR Classic OD (GT-OD) today and the Aeon is much noisier. Same cables, same power supply, and I tried switching the order of the two pedals.
It seems to work exactly as it should, pots all sound good (no scratchiness at all) and everything inside looks much better than I could do with soldering, etc.
BUT it turns my guitar into a noisemaker. Turn pedal on, notice background noise. Put my hand near guitar pickup, noise gets louder. It is there whether I am playing or not. Probably picking up the florescent light above me but it doesn't do that with the MXR or my Guv'nor clone.

This isn't 60-cycle hum - popping bridge humbucker into single-coil mode makes very little difference.
I had an LPB-1 like this and I just thought it was something about the design of the EHX pedal and sold it.But this pedal should be nearly identical to the MXR since they are both Tube Screamer circuits without the buffers. It seems to make my guitar very microphonic, even with the volume and gain set to match the MXR.

If this pedal is just not for me I will flip it but if there is some bad component that causes this I will get it fixed before I sell it to anyone else. OR could it be a component value the builder chose? Something to do with input sensitivity?

[Blille]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

It's hard to tell without hearing it but it sounds like it's not working as intended. Maybe it's not grounded properly?

If it's just hiss, usually the culprit is the IC. The quietest I've had is the MC33178 that actually Duncan uses in the 805.

[PFDarkside]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

So many things go into the design of an electrical component outside of the schematic. As Blille says it’s hard to say, but layout, ground plane design, soldering quality, grounding quality, enclosure quality, component selection and more are all contributing factors. The fact that it’s not a one off means the overall design is probably good, but you could have a questionable solder joint, stray wiring, etc. Is the noise the same on battery or power?

[Dave Locher]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

I did not try it with battery. I will give that a shot tomorrow.
It does seem like grounding might be involved - it sounds like the noise you get when a guitar's bridge isn't grounded except it get louder when my picking hand is just above the bridge humbucker. Like my hand is acting as an antenna for environmental noise?

[Blille]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

I did not try it with battery. I will give that a shot tomorrow.
It does seem like grounding might be involved - it sounds like the noise you get when a guitar's bridge isn't grounded except it get louder when my picking hand is just above the bridge humbucker. Like my hand is acting as an antenna for environmental noise?

That's what it sounded to me like. The first thing I would check is the jacks.

Checking with a battery is a good idea as well.

[Hank-]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

Some pedals are designed with more thought around cleaning the dc input & overall ground plane schemes that help reduce noise. If ya op amp is defective then you would get static/cracklong/sputters/hum/hiss. If ya grounding is bad then touching any metal parts on the guitar will not make it disappear. With drive pedals the noise gets amplified so some pedals tend to be noisier than others. If the grounding on the pcb is problematic then it could be a cold solder joint.

I get that effect where i brign my hand closer on the top area of the pickups or behind/front of the control cavity and its like i'm radiating interference from my body lol. Its less in volume if my other hand in touching the bridge or my bare foot is on tge body of a pedal. I have this off to old building grounding & nearby transformers/cell towers at my place.

[Dave Locher]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

Fixed!
I noticed that the input jack was making physical contact with the pcb for the switch. I loosened it, rotated it slightly, and tightened it back down. I also put a piece of tape over the battery jack. That solved the noise problem.

I still don't like the pedal as much as my Classic OD; already listed it on eBay. But at least I don't have to worry about passing on a faulty pedal.

[Blille]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

Fixed!
I noticed that the input jack was making physical contact with the pcb for the switch. I loosened it, rotated it slightly, and tightened it back down. I also put a piece of tape over the battery jack. That solved the noise problem.

I still don't like the pedal as much as my Classic OD; already listed it on eBay. But at least I don't have to worry about passing on a faulty pedal.

Nice!

Glad it was an easy fix.

[Dave Locher]

Re: What makes an OD noisy? (NPD is it defective or just not for me?)

Nice!

Glad it was an easy fix.

Everyone's comments helped. I started with the most basic thing. Anything more complex would have been over my head!
Thanks to all.