High Pitched Oscilating from TS Clone  [SOLVED]

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benmarshall
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Post by benmarshall »

Hi, I'm hoping someone can help me identify the high-pitched oscillating sound I am experiencing with a Tube Screamer clone. Interestingly I have now heard this same phenomenon with two different TS pedals having just returned a Behringer "Tube Overdrive" for this exact reason. I am now getting the same problem with a Demon Tube Screamer clone.

I've recorded the sound, attached and also here: https://www.sndup.net/9bjt

It's loud when the TS is toggled on (I toggle the pedal in the clip), and the level does vary with volume/gain knobs (I move these towards end of clip). It is still audible in the room when the effect is toggled off, but only when the amp is cranked up.

The problem is present as soon as the pedal is powered from a DC supply. Same problem with just that pedal into the amp, or in a chain (all pedals powered from single supply). With the Behringer it disappeared when powered from battery but Demon doesn't have that option and I don't have a battery clip adapter cable at the moment so cant test. If the DC jack is removed from the pedal the sound disappears, even if it's still in a chain of other pedals.

Does anyone know what this is and how to get rid of it?

Thanks!
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stolen
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Post by stolen »

Heya! This issue can come from a lot of things, and it's kinda hard to debug remotely without more information:

Does the pitch change when you turn gain or tone? Is there a gain/tone setting where it suddenly stops completely?
What power supply are you using? Did you test it with other pedals?

It could be a line filtering problem. If you have a large electrolyte (47u/25V or similar) at hand you could try bypassing the DC jack with it (make sure it's installed in the right polarity). If that resolves or changes the issue the manufacturer might've saved some parts expenses there.

All the best!

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CheapPedalCollector
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Post by CheapPedalCollector »

You can still hear it when the pedal is not engaged, get a different power supply.

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phatt
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Post by phatt »

Agree it's most likely a dodgy power supply.

If you have a Switch-mode power supply (Now very common) some are poor quality and some folks unknowingly use psu's that are not really designed for audio use.
You will likely need to research a better psu system
Phil.

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benmarshall
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Post by benmarshall »

Thanks for the replies. I managed to pick up a different power supply which has fixed this issue. The original supply was a Mooer branded one (which is advertised as being a low noise pedal supply) which seems like it is just over priced cheapo Chinese trash! Replaced with a Stagg 9v supply instead (which is still a budget option) and high pitched noise has disappeared. Interestingly (at least to me) if the Mooer power supply is left plugged into the multi-socket but no powering anything I still get the noise. I guess the Mooer is spewing noise onto the mains loop as well as onto the DC output?

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