[sdiy]Do you need to add more functions to your favorite LP4P VCF ?

[m.bareille at free.fr]

>  By the way, are you using a sw based spectrum analyzer?  I'd be interested in
>recommendations for a PC based analysis tool.

Yes, Spectralab... Limited only by the sound card performance here a Delta 1010
without pretentions. It is good enough to see what's happen in real time  into
the audio BP ... I cannot afford the hardware ones neither an Audio Precision
System like most of us i think...

 It
> would be interesting to run A/B comparisons of a perfectly adjusted VCF
> next to a "detuned" VCF.  Is this amount of variation important or just
> so much nerd talk?

Well more accurate ne the matching more change to get a perfect thing... 1%
resistors sound acceptable to me, at least sonicaly...May be my opinion will
change after passing the thing trough the Spectrum scope...But i also think that
if a good repeatability  is required for polyphonic use a closer matching could
be a good thing.

I have an Agilent multimeter able to match resistors over 0.1% without any
problems... so building a hi accuracy Extrapole isn't really a problem to me...
I will let you know the results when done ... As usual , please be patient !

Now i stop blablabla ,and i go to plug the filter into the Spectrum machine :)


Cheers,

Marc B.