[Fpga-synth] music-dsp list thread about Filterbanks

[Scott Gravenhorst]

"The making of synthesizers in FPGAs." wrote:
>Scott Gravenhorst skrev:
>> Is anyone here watching this?  
>> 
>> I'd like to try my hand at this in an FPGA.  Possible?  What would be the
>> minimum size device to try this?
>
>Depends on what detailed variant of filter you want to use and how many 
>bands. Doable? Probably.
>
>What topology is it? Give me a pointer!
>
>IIRs in some smart combination is probably what I would do.
>

It was my thought as well, but certainly not an experienced one.

My own purpose would be to include a filterbank as part of a digital synth, the filter
hanging off of the synth's output.  I can guess that my Spartan-3A DSP 1800 board should
have an FPGA large enough for a decent polysynth with a filterbank.  

Would the filters needed be of a type such as an SVF or a 4 pole such that higher sample
rates are desirable?  

I may be thinking incorrectly - because of the recursive structure of such filters, I
had thought that they are IIR types, but I don't know for sure...

-- ScottG
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-- Scott Gravenhorst
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