II. Operation
Getting Started
A good way to start is to first turn the knobs to their default settings: Shuffle, Skip, and Rotate all the way down (counter/anti-
clockwise); Slip and PW turned to center. Also, press both buttons off so that 4x Fast and Mute are not engaged. This is the
default setting for an SCM with no breakout and nothing plugged into Slip or Rotate.
A fun sample patch to try is to run a slow clock into the SCM's clock input, and use the S8 and x8 jacks to open two different
VCAs, Low Pass Filters or Low Pass Gates. Run an oscillator or some sound source into both VCAs/LPGs and mix the
outputs together so you can hear both at the same time. Now on the SCM Breakout, turn Rotate, Shuffle, and Skip all the
way down. Turn PW to 50% and adjust to suit your ears. Now play with Slip, slowly turn the knob along its full range and
listen to how every other beat from the S8 jack lands later and later as you turn Slip up. Now nudge Shuffle up until the beat
pattern changes. Play with Slip some more... keep nudging Shuffle up and playing with Slip. Once you get a feel for all the
possibilities with those two knobs, start playing with the Skip knob: you should hear some beats drop out of the S8 sound but
the x8 will continue thumping steadily along.
Using CV and the Knobs at the Same Time
To modulate a parameter, you can simply turn the knob until you get the desired result. Also, you can feed a CV signal into
the associated jack. The jacks and knobs interact as follows:
Skip, PW, Shuffle:
The knob sets the offset, and the jack signal is added to the knob's setting (or subtracted when
there's a negative voltage on the jack)
Rotate, Slip
jacks on SCM Breakout
: The knob attenuates the jack's signal. Turning the knob down all the way will
make the jack do nothing.
Rotate, Slip jacks on main SCM:
Running a signal into these jacks will
add
to the attenuated signal set by the
knob and breakout's jack. In this way, you can plug into the main SCM's Rotate or Slip jack and use the knob as an offset
(with nothing plugged into the breakout's jack)... or you can plug into the breakout and not the main module and use the knob
as an attenuator.
Using the buttons and jacks
The 4x Fast button and the Mute buttons act as inverters if something is plugged into the jack. This is very useful for creating
complex patterns by connecting RCDs and SCMs together.
III. Description of Controls
CV Shuffle
CV Shuffle is closely related to CV Slip, which is described in the main SCM manual (download from
http://www.4mspedals.com/scm.php
). While Slip controls the amount that certain beats are pushed forward in time, Shuffle
controls
which
beats are slipped. The default setting is every other beat (Shuffle at minimum). As you turn Shuffle up, first
every third beat will be slipped, then every fourth beat, fifth, sixth, and finally at a certain point in the knob's range, every
seventh beat will be pushed forward.
From the this point in the range to the maximum, Shuffle behaves differently. Instead of pushing just one beat forward, it
pushes
groups of beats
forward. So at first a group of two beats are slipped, then a group of three, etc...
CV Skip
CV Skip is used to drop beats out of each measure. The concept of the measure is based on 8 beats. The jacks that output
less than x8 are considered to be the first “n” beats of the measure (e.g. S5 jack is considered to be the first 5 beats of a
measure).
With Skip at minimum, all beats are played. As you turn the Skip knob up or apply a positive CV, more and more beats will be
dropped out. The pattern of dropped beats is determined by a lookup table in the SCM's code. Each CV voltage corresponds
to a particular pattern in the lookup table. There are 128 entries in the table, which range from 0 beats dropped, to each one
of 8 beats dropped, to every permutation of 2 dropped beats, to every permutation of 3 beats dropped, to (nearly) every
permutation of 4 beats dropped out of an 8-beat measure. Then the table is inverted, so that it continues to 5, 6, and 7 beats
dropped. Dropping all 8 beats is avoided, since the Mute feature has this same functionality.
CV Pulse Width (PW)
Pulse Width is a very useful feature that affects all 8 output jacks. With PW at minimum, each jack will output a very short
pulse, about __ms. This is enough to trigger most other modules, but no more than necessary.
As you increase PW to about the knob's center setting, the pulse width will be 50%, which is a nicely balanced square wave.
At this setting, the amount of time the waveshape spends being low (0V) is equal to the time it spends being high (+10V).
