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Light sensitive drum trigger

andbrux

May 24, 2010
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May 24, 2010
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Hello,
I've just got my hands on an akai me35t trigger to midi unit to trigger drum sounds.


I'm pretty new to this stuff, but i've made some piezo drum triggers for it (i know its very simple but i felt a tiny bit of pride...) which work just fine.

I've been thinking of other ways to trigger samples/drums etc and came up with the idea of using a cheap maplins strobe light
and a photocell/photodiode/photoresistor (not sure which!) to create a pulse to feed in to the trigger unit.

I've got a few queries before I attempt to do this, If anyone could help i'd be really grateful:
1) I've noticed most photocells seem to use led's as the light source. Would i have to use something a bit more industrial standard if i'm using the strobe as a light source (i want to use this on stage for a visual effect) ?

2) What would be the best way to provide a suitable voltage output that could be used by the trigger unit (the manual says it takes inputs ranging from min -40dbv to max +18dbv impedance 22k ohms) i.e would i need to connect a battery to the circuit?

3) how could I add a sensitivity control to the circuit so that it would ignore changes in ambient lighting and just react to the strobe light source?

4) How could i ensure the pulse/trigger will be a short 'one-shot' signal and will have a fast enough recovery time (i'm thinking having the strobe on its fastest setting would provide rapid fire machine gun-esque triggering)



i think it could be quite easy, but i'll probably be proved wrong.
If any of you wizards could help me out with any suggestions for circuits i'd be massively grateful. In fact, seeing as i'm a novice, if anyone could suggest complete circuits i'd be even more grateful and do some good deeds in return ;).

thanks in advance!
 

Resqueline

Jul 31, 2009
2,848
Joined
Jul 31, 2009
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2,848
I'd believe a super-simple photo transistor setup would work. AC coupling on the output would take care of ambient changes, and a pot on the base for sensitivity.
You could use optical filters for sensitivity to specific colors.
 
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