vocoders

[Kirke Sonnichsen]

Indistinguishable? I must strongly disagree! More bands does
not necessarily make a better vocoder. As you divide the
spectrum into narrower slices, the design of the filters becomes
increasingly more complex. Not to mention that most vocoder
algorithms in low cost multi-effects boxes have a linear
distribution of band "centers" (which is less than optimal for
speech synthesis) and don't have voiced/unvoiced sections!

The 14 band vocoder "object" in the Nord modular series is a nice
exception. No voiced/unvoiced detector but, as it uses a little
less than 50% of the processor bandwith you can build one
relatively easily out of the filter and logic objects provided.
I've heard a rumour that it was designed by Felix Visser. Has
anyone else heard this?

While I'd bet in the near future we'll see some nicer digital
vocoders, I have yet to hear one that begins to rival the
inteligibility of the Synton 221.

- Kirke
(vocoding for dollars)

>
>You can pick up Boss SE-50 effects boxes for $50 nowadays and they have a
>built in 22 band vocoder. An analog implementation would require several
>hundred dollars in parts, and the results would be indistinguishable from
>the $50 DSP unit.
>
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