[sdiy] FPGA digital audio

[Paul Maddox]

JB/Grant,

> > Are there any other designs for digital oscillators besides the classic
> > indexed accumulator?

is this the same as the Phase accumulator oscillator?
sounds like it could be..
This seems to offer best overall performance and give that 32Bit wide SRAM
inside an FPGA isnt hard to find/use its pretty much a standard..

> > I was thinking a digital implementation of a counter wavetable driver.
It
> > seems like with 1 nanosecond clock speeds, a high resolution variable
> > divider driving a counter would allow sub-hertz resolution.

could be..
But you could do better with a PAO..

> The project I'm working on presently (at least when I can find 5 minutes
> for it) is about the minimal hardware structure to implement many
different
> functions, including dig osc of course.
> At some point I realized that the same structure can be used to implement
:
> - VCDO & VC-spectrum VCDO
> - VC-granular synthesis (based on WT or samples)
> - VC granular reverb
> - VC additive synthesis (which is just a specific form of granular
synthesis)
> - etc etc

sounds like an interesting project.

> At first I'm planing to work with separate chips (at least 1 ROM,  1 RAM,
> 1 multiplier, 1 fast uC, A/D & D/A and a few latches), and when I reach
> something, then I may try to impletent it into FPGA.

hehe, its worth it, once you can get the hang of it, so Im told, you can
almost anything with an FPGA..

> If anyone is working on anything similar, I'd gladly share any experience
> - (at least when I can find 5 minutes for it    ;-)

Im working on two things..
a polysynth useing wavetables
and a digital modular concept called 'opensynth' which could be the basis
for such an open ended system like the one you describe JB..

Best wishes
Paul Maddox
_______________________________________
Wavesynth home page;-
    Http://www.wavesynth.com
Modulus synthesizers home page;-
    Http://www.modulus.wavesynth.com
PPG Synthesizer pages;-
    Http://www.PPG.wavesynth.com
Opensynth Project;-
    http://www.opensynth.wavesynth.org/
Waveterm C Project page;-
    Http://www.waveterm.com