Sep
29
Update here:http://kemptonmooney.com/2011/04/pure-data-midi-note-on-off-solution-update/
Last night I had a little down time after a visit from my cousin, and decided to create a synthesizer using pure data. I put together an additive synth using two wave generators. There are various controllers for wave form (including a table option where you can draw the wave form), how the waves are mixed together, and effects like flange, delay, and distortion.
I did run into a problem with midi implementation that I have run into before having to do with note off sends. The synth is a monophonic (generating one tone at a time) and if two midi keys are held at the same time, the last key to be pressed controls the tone. However, if you let go of the first key, it sends a note off message, ending the tone and making for some odd behavior if you are playing a keyboard by hand.
So for example, if you play a C, and still holding the C down, you play an F, the tone changes from C to F. However if you let go of the C, the synth stops emitting the F tone, even if you are still holding the F key down.
I believe I have found a solution to this, but it is a little convoluted and would love to find a more efficient solution. Below is a link to a diagram of the solution using PD objects. Feel free to use the solution in your own work and if you come up with something more efficient, I’d love to hear about it.
