You are here

Getting tingling/shocks from effects pedal.

All about the tools and techniques involved in capturing sound, in the studio or on location.

Moderator: Moderators

Getting tingling/shocks from effects pedal.

Postby Arpangel » Sat May 01, 2021 7:54 am

This hasn’t happened before, my Big Sky pedal, it feels like a tingle every time I touch it, and if I accidentally brush by it with my arm, it hurts, like a small burn, there is no spark or click, like with static.
It does it when no signal leads are plugged in, just the PSU, as soon as it’s connected to the mixer this tingling goes away.
I put my multi-meter on the case to see if there was a voltage there, but nothing.
User avatar
Arpangel
Jedi Poster
Posts: 7773
Joined: Sat Jul 12, 2003 12:00 am
That would be an ecumenical matter.

Re: Getting tingling/shocks from effects pedal.

Postby Wonks » Sat May 01, 2021 8:14 am

It sounds very much like the case voltage is floating, not tied to a ground reference. It can happen with double insulated PSUs. Or faulty single insulated ones.

When you touch the pedal, you then bring the case to the same potential your body’s at. But there’s enough of a voltage difference to cause an initial shock until the potentials have equalised.

Plugging in a cable to a mixer gives it a ground reference, and even a multimeter’s high input resistance is enough to give it a ground reference after an initial voltage spike (which will be too quick to see on a digital meter), so you won’t register any voltage reading.

What type of PSU does it have? Any sign of damage to the PSU leads?
User avatar
Wonks
Jedi Poster
Posts: 11615
Joined: Thu May 29, 2003 12:00 am
Location: Reading, UK
Correcting mistakes on the internet since 1853

Re: Getting tingling/shocks from effects pedal.

Postby Arpangel » Sat May 01, 2021 8:22 am

Wonks wrote:It sounds very much like the case voltage is floating, not tied to a ground reference. It can happen with double insulated PSUs. Or faulty single insulated ones.

When you touch the pedal, you then bring the case to the same potential your body’s at. But there’s enough of a voltage difference to cause an initial shock until the potentials have equalised.

Plugging in a cable to a mixer gives it a ground reference, and even a multimeter’s high input resistance is enough to give it a ground reference after an initial voltage spike (which will be too quick to see on a digital meter), so you won’t register any voltage reading.

What type of PSU does it have? Any sign of damage to the PSU leads?

The PSU came with the unit, it’s a 650ma one, no damage, I don’t have another one of that value to test it with, I’ll try and have a root around and see what I can find. My MXR ISO Brick doesn’t go up to that rating.
User avatar
Arpangel
Jedi Poster
Posts: 7773
Joined: Sat Jul 12, 2003 12:00 am
That would be an ecumenical matter.

Re: Getting tingling/shocks from effects pedal.

Postby Folderol » Sat May 01, 2021 9:17 am

If it's a tingle rather than a zap it's definitely leakage, and I'd recommend getting rid of it ASAP. It might just possibly not get worse, but why take the chance? In the meantime get into the habit of having it always connected to something grounded before plugging it into the mains.
User avatar
Folderol
Jedi Poster
Posts: 13020
Joined: Sat Nov 15, 2008 1:00 am
Location: The Mudway Towns, UK
Yes. I am that Linux nut.
Onwards and... err... sideways!

Re: Getting tingling/shocks from effects pedal.

Postby Wonks » Sat May 01, 2021 9:26 am

I think Folderol meant the PSU, rather than the pedal. Any PSU of the same voltage type/value with a 650mA rating or above, and the same connection polarity will work.
User avatar
Wonks
Jedi Poster
Posts: 11615
Joined: Thu May 29, 2003 12:00 am
Location: Reading, UK
Correcting mistakes on the internet since 1853

Re: Getting tingling/shocks from effects pedal.

Postby Arpangel » Sat May 01, 2021 9:37 am

Wonks wrote:I think Folderol meant the PSU, rather than the pedal. Any PSU of the same voltage type/value with a 650mA rating or above, and the same connection polarity will work.

Thanks, I’m going to try another supply, I’ll have a look around.
User avatar
Arpangel
Jedi Poster
Posts: 7773
Joined: Sat Jul 12, 2003 12:00 am
That would be an ecumenical matter.

Re: Getting tingling/shocks from effects pedal.

Postby Arpangel » Sat May 01, 2021 11:15 am

OK, just looked on the Strymon website, it says you need a minimum of 300ma for the Big Sky, I thought it had to be exactly 650ma so I’ve used one of the 450ma outputs on my ISO Brick, it works fine, and no tingles, indicating a fault as you say, with my other PSU.
User avatar
Arpangel
Jedi Poster
Posts: 7773
Joined: Sat Jul 12, 2003 12:00 am
That would be an ecumenical matter.

Re: Getting tingling/shocks from effects pedal.

Postby Wonks » Sat May 01, 2021 12:00 pm

Good news. A PSU isn't costly to replace (if you even need to now) and you've made it safe again.
User avatar
Wonks
Jedi Poster
Posts: 11615
Joined: Thu May 29, 2003 12:00 am
Location: Reading, UK
Correcting mistakes on the internet since 1853

Re: Getting tingling/shocks from effects pedal.

Postby Arpangel » Sat May 01, 2021 12:15 pm

Wonks wrote:Good news. A PSU isn't costly to replace (if you even need to now) and you've made it safe again.

:thumbup:
User avatar
Arpangel
Jedi Poster
Posts: 7773
Joined: Sat Jul 12, 2003 12:00 am
That would be an ecumenical matter.

Re: Getting tingling/shocks from effects pedal.

Postby Albatross » Sat May 01, 2021 1:15 pm

Is it one of these?

Image
Albatross
Frequent Poster
Posts: 1609
Joined: Sun Jul 26, 2015 12:00 am
Location: Airstrip 1, Eurasia

Re: Getting tingling/shocks from effects pedal.

Postby Martin Walker » Mon May 03, 2021 11:22 pm

:bouncy:
User avatar
Martin Walker
Moderator
Posts: 17657
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK