[sdiy] Vocoder dumb idea of the night

[Tom Arnold]

On Wed, May 14, 2003 at 10:04:12AM +0200, Czech Martin wrote:
> A 2N order bandpass has N*6dB fallof for higher, lower frequencies.
> 2nd order means 6dB, 4th order means 12dB. Arround the peak it can be more
> due to high Q.

I dont know why I always get Order and Pole confused. *sigh*

> Switchers can serve well for the analyser part. In the synthesis part they
> could cause clock feedthrough problems.
> In both sections there could be alias problems. After all, they are 
> sampling structures.
> Perhaps better, if you combine them with a normal 2nd order bandpass
> for anti alias/ clock reject.

I'm using some SCFs right now as anti alias filters in a digital delay
I'm playing with and it seems fine, however I do note that theres alot of
other circuitry around that could be masking any additional noise.
( trying to make a new EH16 from modern available parts )

> Some 100 mails before there was a short discussion on vocoder banks
> together with some very interesting links.

Scrolled back and found it.  That was right when I started working again
and got behind in my emails.  Now to find that 1968 paper...

Thanks!

-- 
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 - Tom Arnold -       When I was small, I was in love,                  - 
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