Effects pedal controller

[shawsofhell]

Hi I want to build a pedal controller to control about 8-10 pedals and with proably 16 different patches. I have seen one floating around b4 but tht only allowed 8 patches i think it was at geofex and used the 74C373 Octal Latch. Is there anyway to wire this to get more patches? Also what sort of relays do you guys recommend?

[smoguzbenjamin]

I wouldn't recommend any relays. Any relay that I have tried was noisy and it made an obvious 'click'. Not nice. You could try digital *shiver* and use a PIC chip to control the patches.

[Mike Burgundy]

When the thing is wall-wart fed, relays aren't any problem at all. Just don't expect to run it of a 9V battery.
You could either go for some kind of logic controller - PIC comes to mind - or do something really nifty with DIP-switches. Didn't GEO have something on this? Yes!
Should be very possible to expand that to more patches: either find a bigger controller chip in the same family and use the same concepts, or slave one 8-patch controller to a patch of the first controller to get 15 patches.
Something like that.

[shawsofhell]

So does every one have these problems with relays (that is they are noisey and click)? The relays I'm going to use are British Telecom approved does this mean their probably decent?

[R.G.]

i think it was at geofex and used the 74C373 Octal Latch. Is there anyway to wire this to get more patches?

Yes. You can add another one on to the first and get 16 (I think).

Same wiring, just parallel the clock signal from the 16(!) signal diodes.

Also what sort of relays do you guys recommend?

NEC's EA2 series. Use the slow-down driver circuit as recommended at GEO to avoid clicks.