Sustain Pedal: Change polarity with a custom console?

[richardein]

Hi, I have a Roland sustain pedal and am trying to use it with an Akai LPK25 Wireless MIDI keyboard. Problem is, the polarity is the opposite of what the Akai needs: the keys sustain when it is not pressed down and the keys shut off when it is pressed down.

I've tried the trick of plugging/unplugging. It doesn't work.

Question: can this be fixed in custom consoles? If so, is there a tutorial anywhere about how to use custom consoles. The manual is pretty opaque.

Thanks in advance for any help you can give me.

R

[stubbsonic]

And just to cover the bases, by the "plugging/unplugging" thing, I assume you mean:

"Power the unit on with the pedal already connected" Yes? Just wanted to make sure.

Any chance the configuration software has an option to switch the pedal polarity? (You probably already tried that).

When you assign a button in a custom console, there are a bunch of options, including Polarity. I'd say mess around with it, if the above ideas are bust.

[HCMarkus]

Looks like you need a new sustain pedal unless you find a way to switch the data, as you will be attempting... good luck!

Dan R (Employee) over 6 years ago
Hello David,

Thanks for posting. I'm sorry to hear you're having trouble.

There are some sustain pedals, without polarity switches, that will not encounter this problem and cannot be resolved.

This used to be a larger issue some time ago, where certain brands chose one polarity over the other, and then produced their own sustain pedals that would work only for their own keyboards.

What is the brand of the pedal(s)? Do these have a polarity switch or method of inverting polarity?

Let me know and I'd be happy to help!

https://getsatisfaction.com/akai_profes ... l_inverted

[Guitar Gaz]

I bought a new one that had a switch to reverse it as my old one was like yours - M audio fairly cheap - the old one now triggers record from my faderport.

[labman]

Richard, we have an expression pedal that needed polarity changed to work with a certain controller we have. We solved it by using a headphone Y cable and only plugin the pedal into it 'halfway' on one side. HAs worked fine for years.

[CharlzS]

Is there an editor for the unit where you can program the on and off values for the sustain connector? Maybe try reversing those. I have the old Roland pedal and checked it with my Arturia MiniLab. Reversing the on/off values appears to work (checked VI instance and visual controller lane).

[richardein]

"Is there an editor for the unit where you can program the on and off values for the sustain connector? Maybe try reversing those. I have the old Roland pedal and checked it with my Arturia MiniLab. Reversing the on/off values appears to work (checked VI instance and visual controller lane)."

Yes, there is an editor for the Akai LPK25 Wireless but unfortunately, it does not allow editing of the sustain pedal.

I gave up and bought a sustain pedal that allows the polarity to be reversed. Hopefully, Sweetwater will deliver it soon

Thanks, everyone, for your input, and please stay healthy and safe!

R

[HCMarkus]

Richard, we have an expression pedal that needed polarity changed to work with a certain controller we have. We solved it by using a headphone Y cable and only plugin the pedal into it 'halfway' on one side. HAs worked fine for years.

An innovative quick fix... I like it!

That approach (or a re-wire of the attached TRS plug) can work for Expression (continuous) pedals when a polarity change is needed, but when the pedal is ON-OFF (make/break), like most Sustain pedals, one needs to physically change the switch characteristic, or reinterpret the switch within the receiving device. Fortunately, most keyboards automatically do the "switch switch" at startup (You can fool these keyboards by depressing a connected Sustain pedal while turning the keyboard on.) As noted, the OP's keyboard is hard wired, so the pedal must conform to it, rather than it to the pedal.

Sustain pedals with a "polarity switch" actually have two internal contact points, a pedal UP and a pedal DOWN contact. The switch simply chooses which contact point will short its TS plug's Tip and Sleeve.

[labman]

Richard, we have an expression pedal that needed polarity changed to work with a certain controller we have. We solved it by using a headphone Y cable and only plugin the pedal into it 'halfway' on one side. HAs worked fine for years.

An innovative quick fix... I like it!

That approach (or a re-wire of the attached TRS plug) can work for Expression (continuous) pedals when a polarity change is needed, but when the pedal is ON-OFF (make/break), like most Sustain pedals, one needs to physically change the switch characteristic, or reinterpret the switch within the receiving device. Fortunately, most keyboards automatically do the "switch switch" at startup (You can fool these keyboards by depressing a connected Sustain pedal while turning the keyboard on.) As noted, the OP's keyboard is hard wired, so the pedal must conform to it, rather than it to the pedal.

Sustain pedals with a "polarity switch" actually have two internal contact points, a pedal UP and a pedal DOWN contact. The switch simply chooses which contact point will short its TS plug's Tip and Sleeve.

Duh ! Good point Markus! Thats what i get for being sick. Arghhhh....

[HCMarkus]

Thats what i get for being sick. Arghhhh....

Get well soon!

[labman]

Thats what i get for being sick. Arghhhh....

Get well soon!

Thank you Markus.

[SMS]

MIDI Pipe is a dandy little utility, it's donation-ware.

http://www.subtlesoft.square7.net/MidiPipe.html

It should work, does amost anything possible to a MIDI signal.