LEDS to my edrums

[Roboticinfo]

Whats up everybody!!

Well I am finishing my electronic drum set and I want to interface 8 leds,
NOW thats simple of course. Although I want 8 LEDS to light up every time I hit the drum. The electronic drum uses a piezo element and maybe I can use that, I don't know. Does anybody have any Ideas for this project?

 

[Blueteeth]

Hi,

Edrums eh? I've hoping to build some soon, haven't played drums in years...

Anyway, I can see two relatively simple ways to do this:

1) connect the MIDI OUT form your drums to a circuit, which reads the messages and makes various outputs high, namely LED's. This would need a microcontroller to read the midi, some MOSFET's to control each 'group' of LEDs, and is probably overkill.

2) For each drum sensor (your piezo element) connect its output to an opamp voltage follower, to give it a massive input impedence (so it doesn't draw the signal away from the circuit that reads the sensors and sends out the midi messages) and a comparator. The output of the comparator should have a capacitor to ground, say, 1uf? so that the breif 'spike' from the sensor lights the LED's for a bit longer, otherwise they would flash very quickly. Again, for 8 LED's, you'd probably need a MOSFET driver, and depending on the LED colour, and power supply available, try to run LED's of the same type in series.

That sounds complicated, but it really isn't, its just you'll need a circuit for each 'drum'. Each 'drum' would require 2 comparators (or 2 opamps, configured as comparators) both are available very cheap, in dual packages.

If the 'Edrum' is completely custom built, with a microcontroller, and you've got spare I/O pins, you could modify the code/circuit to output a pulse every time a particular drum is hit.

Theres some idea's, I will try to be of more help, given more information, wicked idea btw....especially if your drum heads are clear....they'll light up every time you hit one

Blueteeth.

 

[benwied]

hi,
this is pretty much what i want to do but im not interested in the drum triggers serving the purpose of triggering audio at all. jsut turning flashing the leds.... how do i do this??

thanks
ben

 

[Blueteeth]

Well, if you've already got 'midi drums' then their trigger output could just be hooked to a comparator...one per drum head. If you have acoustic drums you'll have to add a piezo element to each head, then to a comparator. The second approach is a bit dirty, but as you said, just for triggering LED's should be fine.

-Blueteeth