MXR Carbon Copy making horrible noises

[robbb]

Bought an MXR Carbon Copy on eBay for a decent price. However after I start using it I get this horrible sounding high pitched echo that gets faster and faster until it's stealing/whining at a high pitch. It gets worse the higher up the "Regen" knob is turned, especially when the "mix" knob is also at anything other than at the lowest possible setting. The pedal also sounds like something is rattling inside but when I opened it up it was just the battery jack that was moving around.

I can't (or really don't want to) use the pedal anymore because the noise happens so frequently and is so absolutely horrible. Does anyone know what might be causing this and/or how to fix it? I'm only using the one pedal, so there's no chain. I have an MXR branded power adapter. Thanks for any help. It's really appreciated.

 

[Believer7713]

Try it with a battery. Make sure you aren't getting DC interference or dirty power interference.

 

[AntStrat]

What bunnyman above said.

Does it do this with all three knobs turned down low?

 

[robbb]

With a battery inside it still happens just not as intensely, which is interesting. It seems to be the "regen" knob that causes the problem.

I think I'm just going to send it to Dunlop and hopefully they can fix it for a reasonable price.

 

[robbb]

What bunnyman above said.

Does it do this with all three knobs turned down low?

No, only when I turn the Regen knob up. When the knobs are all low there's no sound.

 

[Butcher of Strats]

Yeah turn down the knob that makes it sound bad when turned up!
Oscillation!

 

[robbb]

Yeah turn down the knob that makes it sound bad when turned up!
Oscillation!

Yeah but it shouldn't make the noise at all. Oscillation is a good way to describe the sound. Anyway the guy I got it from is refunding my money so I lucked out at least with that.

 

[Wound_Up]

Yeah but it shouldn't make the noise at all. Oscillation is a good way to describe the sound. Anyway the guy I got it from is refunding my money so I lucked out at least with that.

Good because it's definitely not right. I have a Carbon Copy clone and it only does stuff like that when everything is maxed out.

 

[Butcher of Strats]

Yeah but it shouldn't make the noise at all. Oscillation is a good way to describe the sound. Anyway the guy I got it from is refunding my money so I lucked out at least with that.

It may indeed be a defective pedal, but oscillation is a thing a delay pedal may do, and some even think that is a feature, for spaceship effects but by playing with the settings to control it.

 

[Butcher of Strats]

The first time I tried an old DM2 back when they were not old yet, a shop guy was all excited to show me the oscillation feature whenntou turned up the regen knob, which makes the repeats feed back into the original so it gets louder and louder and starts shrieking.
I could not see how that was a plus.
But it is normal for many AD pedals.
Some the designers or AD pedals decided to make that impossible by limiting max regennor repeats, because in shops it could appear the pedal was broken or just really sucked.

 

[Believer7713]

With a battery inside it still happens just not as intensely, which is interesting. It seems to be the "regen" knob that causes the problem.

I think I'm just going to send it to Dunlop and hopefully they can fix it for a reasonable price.

I've sent a few pedals to them over the years and they have been great! They always sent me either replacements or repaired them free of charge. They, at least used to, like to keep their customers returning.
I know they would laugh at me if I sent mine in now since I modded the mess out of it. I built a Molten Voltage Delaytion controller for it before MV stopped selling the kits. I wanted tap tempo and I was several years before MXR released the Deluxe model. Then I added an infinity switch. It now looks like this... all three boxes.

 

[Believer7713]

@robbb how hight is the regen knob when strats happening?

 

[Guy Incognito]

My delay pedals also make horrible noises. However, in my case they are just repeating what's going into them.

 

[robbb]

The first time I tried an old DM2 back when they were not old yet, a shop guy was all excited to show me the oscillation feature whenntou turned up the regen knob, which makes the repeats feed back into the original so it gets louder and louder and starts shrieking.
I could not see how that was a plus.
But it is normal for many AD pedals.
Some the designers or AD pedals decided to make that impossible by limiting max regennor repeats, because in shops it could appear the pedal was broken or just really sucked.

Yeah that's *exactly* how it sounds. You described the sound perfectly. I could see how it could be used as an effect for a spaceship sound but it's nothing I'd ever use in music. It's a pretty terrifying sound especially as it gets louder. I want a delay, maybe I should try digital instead?

 

[robbb]

@robbb how hight is the regen knob when strats happening?

12 o'clock or higher, sometimes even lower if the mix knob is turned up past 12 o'clock

 

[Believer7713]

I will check mine by morning and make sure it isn't going into oscillation at that point. I don't remember it doing it there but I normally don't turn it that high either. I normally only keep mint to about 4 repeats max unless I want oscillation as a segue into another song. Then I step on the momentary infinity button.

 

[robbb]

I will check mine by morning and make sure it isn't going into oscillation at that point. I don't remember it doing it there but I normally don't turn it that high either. I normally only keep mint to about 4 repeats max unless I want oscillation as a segue into another song. Then I step on the momentary infinity button.

So yours also makes this horrible noise? Do all of the MXR Carbon Copys? The most repeats I ever got from this pedal was about 2 and that's with the regen knob turned pretty far up. Also the out of control ever-intensifying oscillation noise would start with the regen knob lower than 12 noon if the mix knob was anywhere besides the lowest setting.

 

[robbb]

The first time I tried an old DM2 back when they were not old yet, a shop guy was all excited to show me the oscillation feature whenntou turned up the regen knob, which makes the repeats feed back into the original so it gets louder and louder and starts shrieking.
I could not see how that was a plus.
But it is normal for many AD pedals.
Some the designers or AD pedals decided to make that impossible by limiting max regennor repeats, because in shops it could appear the pedal was broken or just really sucked.

Would this sound happen with a digital delay? Or do you know of any other analog delays where it's been made impossible? If I get another MXR Carbon Copy will I encounter the same problem? I'd like to have a delay where this would never happen as it's a truly awful sound.

 

[Believer7713]

So yours also makes this horrible noise? Do all of the MXR Carbon Copys? The most repeats I ever got from this pedal was about 2 and that's with the regen knob turned pretty far up. Also the out of control ever-intensifying oscillation noise would start with the regen knob lower than 12 noon if the mix knob was anywhere besides the lowest setting.

Is there any way you could make a short recording of it with your phone and post it for us to be 100% sure what is going on?

 

[robbb]

Is there any way you could make a short recording of it with your phone and post it for us to be 100% sure what is going on?

Unfortunately I can't as I already packed it up to return to the person I bought it from.