[sdiy] Midi2cv8 firmware, SDS-800 question

[Drew Smith (mux)]

	Heya folks,

	Well, I've successfully hax0red the Midi2cv8 into my Simmons SDS-800
drum machine, and I have to say - it rules.  I'm very happy with my
control over the triggering, and the four additional external triggers
are getting a lot of love as well.

	That being said, I understand the trigger length to be 5ms - I was
wondering if anyone's ever played with this value?  I grabbed the
source, and it appears that the length of the trigger is *extremely*
accessable, being a simple variable at the top of the source code.  My
question comes at this point - what next?  I don't have a PROM burner or
easy access to one, and to be honest I'm kinda fuzzy on how to compile
assembler code into a .BIN file.  Is there someone out there who'd be
willing to edit the file, compile, and blow me an EPROM, and ship it my
way (paid, of course)?

	My reasoning is this - the SDS-800 envelopes seem to trigger at the
*END* of the trigger pulse, which I gather is fairly typical of this
kind of circuit.  The shorter the pulse, the punchier the drum sound -
the difference between triggering the kickdrum with the MIDI trigger and
triggering it with the audio from the TR-707 kickdrum is *enormous*...
when I looked into the Concussor modules, they come out into the open
and recommend using a trigger-pulse of 1ms, and no more.  Am I kidding
myself?  Is this total bunk, and the -4ms will be completely inaudible,
or will it add a final little touch of punch to my kick?

	...and lastly, I've got one further mod to do to this machine, I
think.  I'd like to add a second decay envelope to it, which I think is
totally possible (schematics at http://riotnrrd.com/mux/sds800/), but I
haven't been able to find a truly simple and guaranteed-to-be-compatible
circuit for the decay!  Living in Costa Rica, my only real source for
parts is Radio Shack, and even though they seem to be much better
supplied than Radio Shack in Canada, they still aren't what you'd
describe as "fully stocked".  Anyone have a dead-simple decay envelope
circuit that allows for a wicked-fast percussive decay, while only using
a minimum of easily-available parts? :)

	Cheers,
	- Drew.
	
-- 
Drew Smith (mux) <drew at riotnrrd.com>
Encrypted e-mail preferred - finger for public key.
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