Before you buy a pedal, ask yourself this: do I know the polarity of my piano.You're probably thinking something like, "Yeah, sure I do - it's filed in my brain right between my social security number and my bank PIN." But seriously, this is important.Now, you could run off in search of your manual, or you could do yourself a favour and just buy an M-Audio SP-1 Sustain Pedal in the first place and save yourself the trouble.The SP-1 Sustain Pedal has a switchable polarity, so it will work with both your Yamaha and your Roland synth - no problem.