[sdiy] Formant filters, yay!

Elain Klopke functionofform at gmail.com
Thu Mar 9 17:25:43 CET 2017


Yet another question in the string synth line of thinkies. I found a thread
on Muff Wiggler that has a chart of bandpass filter setting for vowel
sounds at various singing ranges:

https://www.muffwiggler.com/forum/viewtopic.php?t=18110&sid=e9ff68db6b9ae389ae845fc9dab582ab

(about halfway down the first page)

I understand calculating the frequency of the filters, and have a handbook
that shows how to calculate the Q of the filters, what I don't quite get is
how to do the dB reduction on the various filters. Would it be a matter of
changing the resistors that mix the various filters into an op amp?

For example,
Tenor 'o'        f1   f2   f3   f4   f5
frequency (Hz)   400  800 2600 2800 3000
Amp (dB)         0   -10  -12  -12  -26
bw (Hz)          40   80   100  120  120

I am, of course, assuming that the signal goes to the five filters in
parallel and then the outputs get mixed back together into, say, an op amp.
f1 would be going through a 100k resistor and then the rest would be
progressively higher values of resistors. Yes?

-Ian
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20170309/60d90b47/attachment.htm>


More information about the Synth-diy mailing list