Manual

4.6 Mid/SideMode 4 THE OXFORD DENOISER
4.6 Mid/SideMode
Mid-Side channel configuration allows better control over the way a stereo signal
degrades to a mono signal. This is important in broadcast where, for example, a stereo TV
program needs to play correctly on a mono TV, or an FM radio broadcast can degrade to
mono in less than perfect conditions, without phase effects. With a Mid-Side signal, you
can simply drop the Side signal to create the mono signal.
You can convert a Left-Right stereo pair of channels into Mid-Side by adding the two
together to create the Mid signal, and taking the difference to create the Side signal:
Mid= Left + Right
Side= Left - Right
In other words the Mid signal is what is common to both Left and Right, and the Side
signal is what is different between Left and Right. You can achieve this in a DAW host by
sending the Left and Right channels to a bus called Mid, and sending the Left and the
phase inverted version of the Right to a bus called Side.
Likewise, you can convert a Mid-Side pair of channels into Left and Right by adding the
two together to make the Left, and Subtracting the Side from the Mid to make the
Right:
Left= Mid + Side
Right= Mid - Side
Although it is possible to convert from Mid-Side to Left-Right and vice versa, signals that
are intended for broadcast should be recorded using the Mid-Side microphone technique,
which ensures there is no actual left-right phase difference.
The Oxford DeNoiser has a Mid-Side mode of operation that causes the plug-in to
de-noise only the Side signal content of the Left-Right signal, leaving the Mid content
alone. The Left-Right signal is first converted to Mid-Side, then the Side is de-noised,
then the signal is converted back to Left-Right.
If you have a recording that is already in Mid-Side format, you can simply de-noise the
side channel as a mono signal. But if the Mid-Side recording has been converted to
Left-Right, you need to use the Mid-Side mode of the DeNoiser to de-noise just the side
contents.
To de-noise just the Side channel is useful in two circumstances. Firstly, for FM stereo
broadcast, switching between stereo and mono modes as signal strength wanes should
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