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Hello,
I'm looking for best DSPs for guitar effects, especially delay/reverb
(1-2s or even more delay).
I can use C55x but I think that it could be too expensive. Maybe some
dedicated DSPs with built-in algorithms could be better? I found:
1) Cirrus CS4811 but it's EOL
2) Alesis AL3201 but I get only 0,8s delay

Any advice?

Thanks for help.
Chojny

chojny <[email protected]> wrote in news:eh9t8e$7s8$1
@news.task.gda.pl:

> Hello,
> I'm looking for best DSPs for guitar effects, especially delay/reverb
> (1-2s or even more delay).
> I can use C55x but I think that it could be too expensive. Maybe some
> dedicated DSPs with built-in algorithms could be better? I found:
> 1) Cirrus CS4811 but it's EOL
> 2) Alesis AL3201 but I get only 0,8s delay
>
> Any advice?
>
> Thanks for help.
> Chojny
>

You may want to consider a low cost Blackfin. These parts have SDRAM
controllers. You almost certainly will need external memory for the long
delays you mention. You might also look at VisualAudio (a graphical tool
from ADI). They have some reverb examples.

--
Al Clark
Danville Signal Processing, Inc.
--------------------------------------------------------------------
Purveyors of Fine DSP Hardware and other Cool Stuff
Available at http://www.danvillesignal.com

chojny wrote:

> Hello,
> I'm looking for best DSPs for guitar effects, especially delay/reverb
> (1-2s or even more delay).
> I can use C55x but I think that it could be too expensive.

Any DSP with that much of memory on the chip will be expensive. Using
the external memory will be more economical. You will need the DSP with
the external memory bus. Consider ADI BlackFIN or SHARC 21065.


Vladimir Vassilevsky

DSP and Mixed Signal Design Consultant

http://www.abvolt.com

On Fri, 20 Oct 2006 09:18:34 +0200, chojny <[email protected]> wrote:

>Hello,
>I'm looking for best DSPs for guitar effects, especially delay/reverb
>(1-2s or even more delay).

Perhaps you don't need a DSP at all. Delay and reverb can be handled quite
easily with primitive functions. About the only thing you might need is a fast
fixed-point multiply. But there are a lot of micros that are not classified as
DSP's that have fast multiply. As others have said, having access to large
amounts of external RAM is much more relevant to your needs.


Robert Scott
Ypsilanti, Michigan

chojny wrote:
> I'm looking for best DSPs for guitar effects, especially delay/reverb
> (1-2s or even more delay).
> I can use C55x but I think that it could be too expensive. Maybe some
> dedicated DSPs with built-in algorithms could be better? I found:
> 1) Cirrus CS4811 but it's EOL
> 2) Alesis AL3201 but I get only 0,8s delay
>
> Any advice?

are you looking for a part (the best part) to build something for a
potential manufactured product or more on the hobbyist - onesies,
twosies scale?

if the latter, you should get a little dev board (along with the dev
software), perhaps from TI (blech) or maybe more preferably one of the
SHArC boards that Al's company can sell. they come all wired up with
external memory (for more delay) and most have A/D and D/A on it or
attached to it. you might have to build a little preamp, maybe not.

> Thanks for help.

FWIW.

r b-j