[sdiy] Raspberry Pi 2 B Synthesizer Project Progress

Kylee Kennedy kmkennedy at gmail.com
Sun Mar 13 01:38:25 CET 2016

Very cool, I was playing with PureData on the Pi 2 and Pi zero this past
week. Pi 2 has a bunch of power for good audio patches while I found the
zero better for clocks and logic patches. I just ordered the Pi 3 for
further testing. Is the Pi 2's audio output from a PWM source or was that
just the earlier Pi 1's?

I would really love to learn how to use the GPIO pins for CV control and
knobs, currently I'm using a Teensy for that function in MIDI mode. Anyone
into PureData should check out MonologX's EcoSystem and Xodular. They are
modular blocks he's design very similar to Max/MSP Beap blocks...also they
are free to download.


On Saturday, March 12, 2016, Scott Gravenhorst <music.maker at gte.net> wrote:

> For those who might be interested in this...
> I've developed what seems to be a stable 32 voice Karplus-Strong MIDI
> synthesizer and I've just measure the latency time (defined as from time of
> receipt of MIDI note-on to start of actual sound signal at the DAC).  This
> was done with a dsPIC and the measurement has a granularity of 6.4
> microseconds.  The latency I measured at first was 24.5 milliseconds, but a
> bit of sleuthing and happy accidents in troubleshooting lead me to the
> source - ALSA buffer size.  Once I reduced it, I attained a measured worst
> case latency of approximately 7.1 milliseconds.  This is with Xorg
> running...  I am currently stress testing it with Chopin Mazurkas and am
> finding no problems.
> This has been quite a road of discovery...  I am motivated now to do
> more.  Next will be adding another synth (bitimbral) or an effects
> processor, perhaps both.  Seems the hardware ought to handle it.
> This code is all in C.  I now have a framework of software for development
> of other synths.
> -- Scott
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20160312/9da33ffa/attachment.htm>

More information about the Synth-diy mailing list