[sdiy] programmable synth module

[Tom Arnold]

On Sat, Feb 11, 2006 at 04:32:36PM -0500, john mahoney wrote:
> There's a module called the PSIM-1 that you can see at
> http://www.synthmodules.com/.  A small number of PSIM-1s exist, but it's not
> what you'd call "readily available," which is too bad because it's a really
> cool module. As cool as it is, though, it did have room for improvement.
> Let's look at the PSIM-1 for inspiration and try to invent a new version of
> a programmable synth module.

One of the major reason I'll never touch a PSIM1 module is this little
snippet of wisdom from the website :
--snip--
PSIM-1 programs are Open Source as described in the GNU GENERAL PUBLIC
LICENSE and made available in the files area of the SynthModules group as
they are developed.  Regardless of what is stated in the code, any programs
developed for the PSIM-1 must remain Open Source and comply with the GPL.
Users are encouraged to share their PSIM-1 programs. 
--snip--

That one paragraph shows such a complete lack of understanding of the GPL (
which I dislike for other reasons actually ) that my brain physically left
my head and went down to the local pub when I read it.  I keep hoping it'll
come back... :-/

Actually cloning a PSIM1 is fairly easy, however I'm not a fan of the
BasicATOM CPUs.  I find them to be a bit too slow for this use, and besides
I stopped programming in BASIC in the 70's. :-)

Personally what I'd like is a nice fast Forth based solution.  To this end
I've played with a couple Atmel based Forth solutions, but they have been
short of my rough goal of 2MIPS.   I reached the 2MIPS goal by figuring out
roughly how many Forth instructions I'd need to process per second to handle
2 44.1khz sampled inputs and 2 44.1khz outputs along with a few instructions
to mutilate the data.  This was arbitrarily chosen with the idea that it
would roughly translate also to 8x10khz -> 8x10khz.

It'll be hard to hit these speeds with an interpreted language and a
cheap/small CPU.  Note I say Difficult, not impossible. 

Oh, and if someone does cook up a solution, make sure its compatible with
licenses other then GPL, or at least make sure you really understand the GPL
before trying to use it...

-- 
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 - Tom Arnold       -  Free Synth DIY webspace http://www.sdiy.org 
 - SynthGeek        -
 - BBD Fanatic      -  "...is it a virus, a drug, or a religion?" 
 - echo evho wjxo   -    Juanita Shrugs. "What's the difference?" 
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