how to build a analog-style frequency divider

flies's icon

I want to build an octave down effect in max msp, one which produces a pulse
wave for every 4 zero-crossings. (omitting DC) any audio wave will cross
zero two times, so in two periods it crosses 4 times. So the problem boils
down to counting zero crossings at sample-perfect timing.

my guess is that it will have something to do with +=~ feeding sah~ or
count~ or something, but i can't figure it out.

of course it's fairly trivial to simply pitch down any input by half, there
are very many ways of doing it, but this particular way interests me b/c it
sounds ugly.

Pierre Alexandre Tremblay's icon

This is how I achieved this... as dirty as possible!

pa

flies's icon

sweet. For some reason i thought that zerox~ output a float, but this is
awesome. ty :)

Isjtar's icon

please don't do that, it doesn't get through to the forum.
can you post it as text?
thanks
isj

roger.carruthers's icon

Isn't there a PerColate object that does this ? Weave~ ?? Not as much fun as building your own, of course...
cheers
Roger

Pierre Alexandre Tremblay's icon

> i assume you attached to your e-mail?
> please don't do that, it doesn't get through to the forum.
> can you post it as text?

I did send a picture of the patch. Sorry, I tried to help ;-)

pa

Max Patch
Copy patch and select New From Clipboard in Max.

---

Peter Castine's icon

On 9-Jun-2006, at 10:30, Pierre Alexandre Tremblay wrote:
>> i assume you attached to your e-mail?
>> please don't do that, it doesn't get through to the forum.
>> can you post it as text?
>
> I did send a picture of the patch. Sorry, I tried to help ;-)

There are times when the image is actually quite helpful (for
instance, trying to demonstrate something that needs a variety of
3POs, or for simple patches where rebuilding is more informative than
mere Copy & Paste). But it is hard on the poor forum readers.

-------------- http://www.bek.no/~pcastine/Litter/ -------------
Peter Castine +--> Litter Power & Litter Bundle for Jitter

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Isjtar's icon

Quote: Peter Castine wrote on Fri, 09 June 2006 10:37
----------------------------------------------------
> On 9-Jun-2006, at 10:30, Pierre Alexandre Tremblay wrote:
> >> i assume you attached to your e-mail?
> >> please don't do that, it doesn't get through to the forum.
> >> can you post it as text?
> >
> > I did send a picture of the patch. Sorry, I tried to help ;-)
>
> There are times when the image is actually quite helpful (for
> instance, trying to demonstrate something that needs a variety of
> 3POs, or for simple patches where rebuilding is more informative than
> mere Copy & Paste). But it is hard on the poor forum readers.
>
----------------------------------------------------
i agree, they should allow it on the forum too. how about the archives? does it get through there?

anyway, thanks for the patch...

flies's icon

small optimization: i think if you just subtract 1 from the bitand~ output
then you can skip the selector and get the same output with a few fewer
signals tied up. (it'd be phase inverted as compared with the selector
output)

but this totally sounds like teh shit. ty.