Why reversed polarity?

[avvie]

Buddy of mine is losing his mind because his SparkleDrive and Catalinbread tremelo are wired reverse polarity. He has a point: why would manufacturors do this when the standard for power supplies is center negative?

EDIT: Since starting this thread the problem has been better defined: pole switching is happening within the effect....positive signal on input becomes negative signal on output. This is not about the power supply polarity, which is how it sounded when he presented it.

 

[ArtechnikA]

Why - I'd guess they had a reason, and it probably has to do with how their circuit board interacts with the case and the socket they used (for some reason).

There is no 'standard' - just a 'convention.'
I've got a bunch of pedals with unusual power connectors. You just have to pay attention. Labels help...

 

[LSMFT6]

Yep. Why bother with batteries and battery compartments when it's way better (unless you're only using one or two pedals) to use a PS?

 

[Downunderwonder]

I don't know if they came up with it but the Boss standard has been chosen by many others. Still a non standard.

 

[MightyMiloQuinn]

Buddy of mine is losing his mind because his SparkleDrive and Catalinbread tremelo are wired reverse polarity. He has a point: why would manufacturors do this when the standard for power supplies is center negative?

Which tremolo is he using? AFAIK the Semaphore is center negative, as is the Sparkle Drive.

 

[iiipopes]

To sell you their proprietary power supply.

 

[SGT. BAKER]

To sell you their proprietary power supply.

I´d understand it if this pedals they worked with an inusual and very rare/strange voltage and amperage than the rest. But usually isn´t the case.

But it´s possible changing the polarity with some reversed accesory cable/wire. And some power supply they have some outputs with reversed polarity, like the Harley Benton Power Plant. Even there´s adapters that it´s possible to do it turning the conector.

 

[cheapbasslovin]

Which tremolo is he using? AFAIK the Semaphore is center negative, as is the Sparkle Drive.

I think the OP's friend might be insane; I'm almost certain these both go nicely on a center negative supply.

Generally I think when manufacturers use non standard wiring their chosen components work best or easiest with whatever non-standard supply they end up using. Modern hardware allows for easier modification of a circuit to bring it into the standard spec, but easier doesn't always mean easy and if a manufacturer has a good enough design that they can sell it in spite of a bad power supply requirement they may decide they don't care enough to change it.

 

[MrLenny1]

There seems to be no standard to this.
I work in Electronics and different manufactures have different
polarity references.

 

[dannybuoy]

Which tremolo is he using? AFAIK the Semaphore is center negative, as is the Sparkle Drive.

I think the OP is talking about using standard adaptors used in most other equipment using center positive, rather than these pedals benig different to each other.

It's just the way it is, it just means you have to buy an adaptor for your pedals instead of re-purposing one that you maybe used for an old router or telephone!

 

[MightyMiloQuinn]

I think the OP is talking about using standard adaptors used in most other equipment using center positive, rather than these pedals benig different to each other.

It's just the way it is, it just means you have to buy an adaptor for your pedals instead of re-purposing one that you maybe used for an old router or telephone!

The standard is center negative. Every pedal I've ever owned has been center negative. The pedals mentioned above are also center negative. I wasn't speaking to proposed question, but to the problem the OP's friend was having. I mean, just on the surface, it would seem silly for Voodoo Lab to make a pedal (the Sparkle Drive) center positive when their own power supplies are most used for center negative.

 

[Slevage]

My guess---
Some digital circuit designs favor "sourcing" inputs and outputs (the + is switched).

Some favor "sinking" inputs and outputs (the - is switched).

Probably easier to layout the circuit board one way or another, depending on component choice, number of connections, and possible circuit noise (not the kind we can hear).

 

[castlev]

could be me but reverse polarity seems haphazard, not that 9v would kill anyone, but a loose reverse polarity plug pulling out and grounding itself to a rack could cause some problems. unless i have no idea what i'm talking about.

 

[KevInDaBassment]

I'd really like to know if there is any advantages to not go center negative. It seems like a stupid move since most of your daisy chain connectors use the standard 9v plug like Boss does. Why go and make something unnecessarily difficult? This was one of the reasons I sold my Proco Rat II and EHX Small Clone. I used them both on guitar, but it just seemed ridiculous to buy them IMO.

 

[Mugre]

There is no "standard" where some rules body like S.A.E. I.E.C. A.E.S. etc have called for one way to do it like pin 2 is "supposed" to be hot on an XLR. It's not a very big deal to turn the polarity with a new plug or an adaptor.

 

[avvie]

Okay, he's not talking about power input; he's talking aboit a 180 degree reverse in the signal path where input signal rises and output signal falls.

 

[ArtechnikA]

Aha - that's not 'polarity' - that is 'phase.'
Buffers tend to do that. I know there are switch boxes and interfaces that can flip phase reversal - but I haven't had to deal with the issue so I can't recommend any specifically...

A search through effects looking for 'phase' will turn up hits tho...

 

[dannybuoy]

I'm with you now! I (we) misunderstood the original post. The issue is nothing to do with power supply polarity.

Each gain stage typically flips phase - simple boosters, many overdrives (e.g. SFT) and my Phase 90 all do it. And yes it is annoying, especially when recording if you want to DI clean bass and mic up amp & fx chain, with the phase flipping all the time.

It's usually just bassists that complain about it since we are more likely to run some pedals in blenders or send a clean DI to the desk than guitarists. Saying that, a guitarist I know had the same issue with an LPB-1 booster in his amp's FX loop which had a blend too.

 

[_Elf]

could be me but reverse polarity seems haphazard, not that 9v would kill anyone, but a loose reverse polarity plug pulling out and grounding itself to a rack could cause some problems. unless i have no idea what i'm talking about.

Neither side of your average 9V DC wall wart adapter (positive or negative) should have a reference to ground, so grounding either the positive or the negative will not cause a short. Only a connection between the positive and the negative of its output will cause a short.

 

[Slevage]

Neither side of your average 9V DC wall wart adapter (positive or negative) should have a reference to ground, so grounding either the positive or the negative will not cause a short. Only a connection between the positive and the negative of its output will cause a short.

Right on---- you can ground any circuit at any point------- just don't do it anywhere else.