Creating And Configuring Mixers - Merging Pyramix User Manual

M&S Stereo Strips
White:
Red:
Blue:
Inverting either Sum or Difference results in the image being reversed left to right.
Note: If the Input meters consistently show S higher than M then either the image is
very wide and unlikely to be compatible for a mono listener or the M and S inputs have
become reversed at some point. Regrettably, this is extremely common when dealing
with location recordings in film and TV.

Creating and Configuring Mixers

If one of the numerous mixer presets does not quite suit your application it is simple to modify an existing mixer,
create one using the Mixer Wizard or design one from scratch. The Wizard can be started from an existing mixer by
right-clicking anywhere on the mixer surface and selecting Settings > Wizard...
What is M&S?
M&S stands for Middle and Side. M&S is a microphone technique which outputs Sum and Dif-
ference signals instead of Left and Right (also known as LR, AB or XY). These Sum and Differ-
ence signals are often known as M&S although this nomenclature is often a source of
confusion...
Sum and Difference signals can be created from a conventional Left, Right source. For example,
by using the Pyramix MS Encoder plug-in.(Please see: MS Encoder on page 232).
Decoding M&S
A Sum and Difference or M&S decoder reconstitutes Left and Right by adding the Difference
(S) signal to the Sum (M) signal to produce Left and adding the phase-reversed Difference (S)
signal to the Sum (M) signal to produce Right. This is often represented as:
L = M + S and R = M - S
Benefit of M&S
In mixing as opposed to recording, the main practical benefit of manipulating a signal in the
Sum and Difference domain is true control over the width of the image. Pyramix can handle
these signals directly thanks to the provision of M&S Stereo strips.
M&S Strip controls
An M&S strip stereo bus send has three controls. The center knob determines the Sum (M) con-
tribution to the Left and Right outputs. The L knob determines the in-phase Difference (S)
contribution to the Left output and the R knob determines the out-of-phase Difference (S) con-
tribution to the Right output. The L&R knobs are ganged by default. To move them indepen-
dently click and drag with the Ctrl key held down.
The Phase of both the Sum and Difference channels can be reversed. The single Ø button has
four possible states:
Black: No phase inversion
Sum (M) channel inverted
Difference (S) channel inverted
Both channels inverted
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