Noise from power supply for effect pedal?

[H]

Has anyone experienced unwanted noise from an effect pedal which appears to originate in the power supply unit (PSU)?

 

My T-Rex Twin Boost has a highish noise floor anyway but if I power it from a PSU I get a strange, high pitched 'helicopter' noise through the amp (either of them) whether the pedal is engaged or not. Same thing with my reverb pedal.

 

It doesn't happen if I use batteries. I have the amp and PSU plugged into the same four-way plug extension. The PSU's earth connection on the plug is made from plastic.

 

Just wanted to check before I spend money on a new PSU.

[DetroitBlues]

That's why people turn to isolation power supplies.. Simple wall wart type power supplies transfer in dirty power that has signal interference. Very common problem for stage use and that's why a lot of musicians use power conditioners and isolation power supplies for the pedals...

[H]

Thanks DB. Perhaps I need to spend some money on a decent power supply system.

 

The UK is supposed to have one of the cleanest electricity systems in the world. I guess there's clean and there's clean

[pegleg32]

Howard, I have had that happen as well. I can't remember which pedal it was, but I remember that I could get it under control by adjusting the pedal settings. It was awhile ago, but I think it may even have been a certain combination of two pedals. Might try some testing there first.

[DetroitBlues]

Thanks DB. Perhaps I need to spend some money on a decent power supply system.

 

The UK is supposed to have one of the cleanest electricity systems in the world. I guess there's clean and there's clean

 

You'd think it would be the same in the US. But its not.

[H]

Howard, I have had that happen as well. I can't remember which pedal it was, but I remember that I could get it under control by adjusting the pedal settings. It was awhile ago, but I think it may even have been a certain combination of two pedals. Might try some testing there first.

Should be easy Don, I've only got two pedals

[JeffB]

What brand is you power supply and how many milli amps or amps is it?

Ive come across a few wall warts power supplies that add noise.

[SouthpawGuy]

Has anyone experienced unwanted noise from an effect pedal which appears to originate in the power supply unit (PSU)?

 

My T-Rex Twin Boost has a highish noise floor anyway but if I power it from a PSU I get a strange, high pitched 'helicopter' noise through the amp (either of them) whether the pedal is engaged or not. Same thing with my reverb pedal.

 

It doesn't happen if I use batteries. I have the amp and PSU plugged into the same four-way plug extension. The PSU's earth connection on the plug is made from plastic.

 

Just wanted to check before I spend money on a new PSU.

 

What brand is the psu ? I got a generic one with multi attachments from a hardware store, turned out the psu was noisy, it emits a high pitched sound when on. I use that one for cameras etc now not for music / guitar. Got a Dunlop DC brick and haven't had any problems with it so far.

[H]

Jeff/Paul, it's a cheapo Chinese PSU which says it puts out 1 amp / 9 volts.

 

Time to spend some cash I guess

[pegleg32]

I agree with you Howard, not too far too look is there? Sounds like power supply ok.

[SouthpawGuy]

Jeff/Paul, it's a cheapo Chinese PSU which says it puts out 1 amp / 9 volts.

 

Time to spend some cash I guess

 

If you don't have a tuner pedal maybe get one that will also act as a power supply for a few pedals. The Boss one will do that, just needs a daisy chain lead to power other pedals. Just a thought.

[TalismanRich]

Most wall warts are simple linear power supplies which can have mediocre noise filters.

 

I grabbed a One-Spot for my few pedals, a TS-9, TurboTuner, Vox wah and a Dano Surf and Turf compressor. It seems to be about the same as with batteries, overall its pretty quiet. The Dano eats through batteries very quickly, so having the PS lets me use it more. 9 volts are just getting expensive.

[tbonesullivan]

maybe you've managed to create a ground loop? all depends on how things are hooked up.

[H]

maybe you've managed to create a ground loop? all depends on how things are hooked up.

The earth pin on the mains plug is plastic so I'm not seeing where a ground loop could be happening.

 

I think I've just been a cheap-ass and bought a rubbish PSU with no noise filtering

[DetroitBlues]

I've noticed on many professional rigs, many pros have voodoo labs isolation bars (power) powering their pedals...

 

[bobmeyrick]

I had a similar problem when running my Strymon Lex off the same psu as a few other things. The problem was sorted when I powered the Lex with its own separate psu.

[H]

I've noticed on many professional rigs, many pros have voodoo labs isolation bars (power) powering their pedals...

 

I have one of these on the way to me as we speak

[tulk1]

I've had this with a JHS pedal. Put it on the pedal board with the DC brick and it was fine. But power up singlely with a One Spot and wow!! Flutter like crazy. And yep - a One Spot. So I took it back to show them. Their pedals do not like the OS. But, get this ... it loved the cheap Danelectro power supply. And a buddy of mine that builds/mods his own pedals for his own board had the same issue with just one of his pedals with the One Spot. Something about a particual component he was using conflicted with something in the way the power was being supplied. Too far above me to describe scientifically. Now, not saying One Spots are bad, because I use them on two different boards. In fact, I use a One Spot to power my DC Brick (the original ps blew up at a gig). My comment is that sometimes internal components on the pedals conflict with the power supplies.