[sdiy] (simple) musique mechanique

[WeAreAs1 at aol.com]

In a message dated 1/7/04 6:33:29 PM, bobby at csounds.com writes:

<<  I got my little automated drum working today (the
batonMaton). This is my first time playing with
solenoids and PWM. :)  

I took a few pictures of it smacking away at 340 bpm.
I thought some of you might be interested.  
http://www.enfason.com/batonMaton

now to make 8 more and add a PIC MIDI Rx. >>

Cool!

I don't know if you knew, but about one year ago there was an article in Nuts 
and Volts magazine about building a DIY MIDI-controlled glockenspiel (or 
xylophone... I can't recall which).  It used solenoids to activate the strikers, 
and I'm pretty sure that it used a PIC processor.  Maybe the PIC code he used 
would be useful to you in getting yours going?  It was probably either 
downloadable or actually printed out in the magazine.  Unfortunately, I don't have a 
copy of the issue, but it's very likely that someone on this list does.

I wonder if there would be a way to make your solenoid strikers be velocity 
sensitive?  Maybe even just two levels -- like the way some earlier Roland drum 
machines allowed you to "accent" a played note.  Would varying the voltage or 
current into the solenoids change their striking force at all?  Also, what 
does PWM have to do with your device?  Are you using a pulsewidth-modulated 
control signal to somehow vary the effective striking force or speed?

Michael Bacich