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Fun with 490s

2004-01-19 by Richard Brewster

I wanted to try something with my two MOTM 490 filters today.  This is 
what I came up with.  Also this is the first sample I've uploaded.  It 
is three minutes long, hope the file isn't too large.  I mistyped the 
title in the MP3, which says "Two MOTM 390 VCFs".  Oh well.

The audio part of this patch is two MOTM-300 VCO square wave outputs 
each through a separate 490, then each through a MOTM-190 VCA driven by 
its own MOTM-800 EG.  This is mixed to a stereo out.  The 490's are both 
set at 2.5 resonance and the FREQ at 7.  The 1V/OCT inputs are not used; 
the filters are not tracking with the VCOs.  The wigglyness is created 
by modulating each VCF with a fairly rapid sawtooth LFO.   I used two 
Oakley Little LFOs here, but the MOTM-320s would work fine too.  The 
sawtooths are negative in slope, i.e. falling most of the time with a 
rapidly rising edge.

The control section is made up of a CGS Infinite Melody quantized with a 
Blacet Miniwave.  The quantized output is shifted by a pair of sample 
and holds, so that one VCO gets the voltage the other just had.  I used 
the MOTM-120R as a pulse divider to drive the gate inputs of the 800s to 
produce the rhythm.  It's all clocked by a MOTM-390 LFO for the main 
tempo.  Every 8 beats a third S&H feeds a new voltage to the Bank CV on 
the Miniwave, which has the Quantizer EPROM installed.  (This third 
random stepped voltage is also patched to the tempo LFO FM input, but 
was not used during this recording. When it is, the tempo changes every 
8 beats too for maximal weirdness.)  I touched nothing during the recording.

I think it makes a nice demo of the timbre qualities of the 490.  It 
sounds really resonant without any other delays or phase shifts introduced.

-Richard Brewster

motm@yahoogroups.com wrote:

>Hello,
>
>This email message is a notification to let you know that
>a file has been uploaded to the Files area of the motm 
>group.
>
>  File        : /Two-490-VCF.mp3 
>  Uploaded by : pugix <pugix@...> 
>  Description : Some fun with two MOTM 490 VCFs 
>
>You can access this file at the URL
>
>http://groups.yahoo.com/group/motm/files/Two-490-VCF.mp3 
>
>To learn more about file sharing for your group, please visit
>
>http://help.yahoo.com/help/us/groups/files
>
>Regards,
>
>pugix <pugix@...>
> 
>
>  
>

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