Soft patch

A soft patch is a mapping between channels and dimmers (or more specifically, DMX channels). This allows you to customise what each channel number does on a lighting desk, by setting the channel of each DMX channel. For example, you can control groups of dimmers with one channel (useful for HLs) or renumber dimmers to move similar functions near each other (for example, have all facelight dimmers together on the desk).

A soft patch is configured on the lighting desk itself, so check you know how to reset and customise it on the desk you are using.

The default patch is usually 1-1, so channel 1 controls DMX channel 1.

Intelligent Fixtures
Another use is with Intelligent Fixtures. Boards which have improved control over intelligent fixtures will need the DMX Channels of the fixtures patched to a profile of that fixture.

This allows better control of the attributes of the fixture. For example, many moving lights use two DMX channels to control a single attribute (one rough and one fine, 16-bit precision). This can not be properly controlled with a tradition lighting desk, as it needs to be treated as a single value.

It also allows the desk to not fade an attribute, which may cause undesired results with some devices.