[sdiy] Filterbank, part deux

[Richard Wentk]

At 00:09 19/12/2002 -0800, Tim Ressel wrote:

>  Rumor has it that CSound was ported to the
>Sharc, that would be a kick-butt thing indeed.

There was a special Sharc version of Csound released around '96. It came in 
the form of a development kit, and cost quite a bit of money at the time. 
It hasn't been upgraded since, and a modern Athlon/P4 runs rings around 
that old board. The old Xanadu test file creaked along at something like 
half real time on that hardware. My Athlon XP 2.1 - already a little dated 
- renders it at something like four times real time. (Yikes!)

Apparently the board was used by certain hardware developers who prefer to 
remain nameless, although if I had to make a guess I'd be thinking about 
either Gem or Creamware.

There are also a load of new opcodes in later releases that can't be added 
to the development kit, which was a closed affair. (Unless maybe you're 
prepared to code *all* of them yourself...)

>My grand plan is to have several global configurations
>available via a front panel control. Extra stuff can
>be downloaded or something. If this is all successful,
>I will make a module out of it. The easy part is doing
>the programming, the hard part is interfacing the DSP
>baord to front panel controls.

I've been doodling a filter bank idea of my own and thinking it makes a lot 
more sense to DSP it instead of building it in analogue hardware. Keep me 
posted how this one works out.

You should check out the Alesis DSP chip I posted a link to a while back. 
It's incredibly cheap, has four stereo ins/outs and runs at 50Mips. They 
already have a 20-channel filter bank implemented, and the code is freely 
available.

Richard