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Two Patching Questions

Two Patching Questions

1999-05-19 by Tentochi

** I want my MOTM LFO SINE to control VCO PWM, but I want the "width" of the
change to be fairly narrow. How do I control the min and max width in this
scenario? Will the knob on the VCO control the center point of the change?

** Can the ADSR EG control the cutoff frequencies of the upcoming filter
modules or do I need a VCA with it? I am guessing (and hoping) for the
former.

Thanks!
Todd

Re: Two Patching Questions

1999-05-19 by JWBarlow@xxx.xxx

Hi Todd:

In a message dated 5/18/99 7:06:13 PM, tentochi@... writes:

>** I want my MOTM LFO SINE to control VCO PWM, but I want the "width" of
>the
>
>change to be fairly narrow. How do I control the min and max width in
>this
>
>scenario? Will the knob on the VCO control the center point of the change?


The WIDTH control is used to determine the initial PW. The PWM control is an
attenuator (i.e., a level control) for the voltage present at the PWM input.
So yes! These two controls will do what you want.


>** Can the ADSR EG control the cutoff frequencies of the upcoming filter
>
>modules or do I need a VCA with it? I am guessing (and hoping) for the
>
>former.

The basic reason there are several CV inputs for frequency control on a VCF
is to do this, or something like it. For example, you may want to use one for
a keyboard (or sequencer) input, a second for an ADSR, and a third for maybe
an LFO, S/H, vibrato out (from the MOTM 100), or ....

As far as using a VCA to gate a CV, this is a very powerful technique! I
think this is often done, for example, for a delayed vibrato effect for a VCO
CV input. The LFO would be used as input to the VCA. The VCA output would go
into one of the VCO FM inputs. A second ADSR would be used to determine the
"way" the LFO would effect the VCO. A simple example, with many more
interesting possibilities.

That's what's great about the modular concept. You can never have too many
VCAs......
or VCOs.....
or VCFs....
or.......
"So John, how's that synthesizer coming? When are you going to finish it?"
Met with only a puzzled look -- why would I want to finish it? There's always
more modules to build.
JB

Re: Two Patching Questions

1999-05-19 by Paul Schreiber

>** I want my MOTM LFO SINE to control VCO PWM, but I want the "width" of
the
>change to be fairly narrow. How do I control the min and max width in this
>scenario? Will the knob on the VCO control the center point of the change?


The WIDTH pot is the initial width (ie width with ZERO PWM control voltage).

The PWM input jack is attenuated by the PWM pot. The initial width swings
narrow/wider
about it based in the input CV.

>
>** Can the ADSR EG control the cutoff frequencies of the upcoming filter
>modules or do I need a VCA with it? I am guessing (and hoping) for the
>former.

Anything can!

Paul S.