audio to trigger (+ to MIDI?)

[Simon]

I would be interested in a similar sort of DIY project to allow the
triggering of MIDI devices using acoustic drum triggers or recorded audio,
to allow playing of MIDI sounds with a real drum kit, or to replace
prerecorded drums with other drum samples.

A drum module like the Alesis DM4 or Roland D5 would do this, but I don't
need the inbuilt sounds, is there a cheaper DIY audio-trigger-MIDI project?

Thanks
Simon
Canberra
AUSTRALIA


>> I'm looking for a way to convert the audio outs of my TR 707 to short
>> trigger pulses for triggering analog drum sounds. I thought about a
>> differentiator but I'd get several pulses with that, or a 555 one shot but
>> I guess I'd get the same problem. Any help would be greatly appreciated.
>
>Before you do that, have you tried just triggering the drum sounds with
>the audio outs of the 707?  Back in the analog days of yore (i.e. about
>6 months ago, before I sold off most of my analog collection) I used to
>sync up a 707 to my 606 and 202, and used the independent outs of the
>707 to trigger the drum sounds on a Tama TS-305 drum brain.  It worked
>like a charm.  The "Attack" control on the 305 allowed me to mix how
>much of the original drum sound could be heard in the output (I think it
>was a simple lowpass filter, designed to work with voltage triggers to
>add more or less "click").  I used a Drumfire with the 707, and also got
>good results.  Maybe some analog drums need a conditioned pulse, but I
>have the feeling a lot of them will work with any good percussive
>sound.  Twin-T filters and the like should be able to trigger from the
>707, with the 707 sounds providing some nice attack coloration.
>
>Sean Costello