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Hi everyone,

Correct me if i'm wrong but as i understood, the Roland SPD controllers pads work like this:

_ on a hit, a switch incorporated into the pad's rubber layer triggers a 'hit' information
_ a piezo located somewhere under a metal layer supporting the rubber switch, senses the hits vibration and provides this hit's intensity information, which is turned into velocity

So these two sensors work somehow in conjunction to register a hit and it's velocity information

is there a way to make this type of triggers work with MD? I never got to try 2 or 3 way cymbals, i only use MD in simple DIY percussions, but it seems like they can be based on this type of switch+piezo conjunction, am i wrong?

thanks for your help!

That's right. It's how piezo/switch pads work and how the module distnguishes between zones. It will work perfectly well with MD and you can have 2 switch zones + piezo zone per stereo input.

Well I have an SPD 8 from back in the day and I don't think it has (nor would it need ) any switches. Are we talking about something else?

Yeah, I forgot to add - I don't have a clue whether the Roland SPD uses switches + piezos, but it is something that can be made to work with MD regardless.

ignotus wrote:Yeah, I forgot to add - I don't have a clue whether the Roland SPD uses switches + piezos, but it is something that can be made to work with MD regardless.

Oh yes absolutely, the general switch/piezo is catered for.

The footswitch (If that is what we are talking about) changes multiple midi notes which is completely different.

airflamesred wrote:Well I have an SPD 8 from back in the day and I don't think it has (nor would it need ) any switches. Are we talking about something else?

I'm not 100% sure, but from what i read, there's a sort of membrane switch incorporated inside the rubber of the pads, something like a net sandwiched between two sheets of conductive foam, the net keeps the sheets apart until a strike occurs that forces them to make contact through the net's holes, from what i understood, everything's placed on a metal sheet underneath which the piezo is sticked, the piezo senses the vibration from the hit. Maybe it's not how the Roland SPD works, i can't tell for sure as i have never torn one apart to look inside!

Looks easy technically, but it seems quite complicated to build a strong one, that could last for some time...

It may be worth the try for me, as i have quite some crosstalk problems in my all-piezo percussion design, this kind of switch+piezo system may improve things a little, not sure though...


Thanks for your help guys!

You could probably do it with conductive sheet rubber, putting some netting between two layers of it. Might be pricey, though it should be durable. You use a stereo input, set it to piezo/switch, raise the threshold of the head input (piezo) to 127 so it doesn't get triggered by crosstalk, while the switch still triggers normally. I tried setting the head note to 0 so it can't get triggered at all but then the switch zone won't work. You could also use the xtalk and xtalk group settings to further isloate the pads.

deuns0615 wrote:I'm not 100% sure, but from what i read, there's a sort of membrane switch incorporated inside the rubber of the pads, something like a net sandwiched between two sheets of conductive foam, the net keeps the sheets apart until a strike occurs that forces them to make contact through the net's holes, from what i understood, everything's placed on a metal sheet underneath which the piezo is sticked, the piezo senses the vibration from the hit. Maybe it's not how the Roland SPD works, i can't tell for sure as i have never torn one apart to look inside!

Well. I didn't know that. More akin to FSR then.
Keep us posted, yhis looks interesting.