Re: Locking a Jam Man to odd time Midi sequence

["James Reynolds" <tritone@dsp.net>]

> Does anyone know a way to lock a Jam Man to a MIDI sequence based on
> an odd time signature? I know it's basically a preset piece but I
> wondered if any of you figured out a way around that limitation.

i accomplished this using opcode's MAX programming environment to bend the
rules of midi sync a bit, but maybe there's an advanced sequencer that also
lets you do strange things with the sync output.

midi sync consists of the message "248" inserted into the outgoing midi
stream 24 times per quarter note.  so, if you have your jamman set at 4
quarter notes per loop, then it's expecting to receive 96 "pulses" before
it restarts the loop.  if you want the jamman to sync to a sequence in 5/4,
have the sync source send the jamperson 96 pulses equally distributed over
the duration of the 5/4 measure.  at 60 bpm (i like 'em slow), a 5/4
measure will last 5000 milleseconds, so you would send the jamman a pulse
every 52.08333... ms.

little detail to worry about:  at least for MAX, the resolution of timing
objects is generally 1ms, so my algorithm actually divides the measure into
durations something like 52ms, 52ms, *53ms*, 52ms, etc., that all add up to
exactly 5000ms.

one complaint i have about midi sync is that it's not channel-specific --
all 16 channels will receive the same sync (damn midi-standard-folks didn't
count on people like me being into polymetrical stuff...)  still, if you
have two or more midi interfaces you can send different sync on each one.

hope this helps...

james