MIDI Show Control - How MSC Works

How MSC Works

When any cue is called by a user (typically a stage manager) and/or preprogrammed timeline in a show control software application, the show controller transmits one or more MSC messages from its 'MIDI Out' port. A typical MSC message sequence is:

1. the user just called a cue
2. the cue is for lighting device 3
3. the cue is number 45.8
4. the cue is in cue list 7

MSC messages are serially transmitted in the same way as musical messages and are fully compatible with all conventional MIDI hardware, however many modern MSC devices now utilize Ethernet communications for higher bandwidth and the flexibility afforded by networks. Other performance parameters are also transmitted such as lighting desk submaster settings using MSC SET messages.

All cues that a media control device is capable of playing are assigned MSC messages within the Show Controller's cue list and they are transmitted from its 'MIDI Out' port at the appropriate show time, depending on the actions of the user and the show controller's internally timed sequences.

All MSC compatible instruments follow the MSC specification and thus transmit identical MSC messages for identical MSC events such as the playing of a certain cue on the media controller. Since they follow a published standard, all MSC devices can communicate with and understand each other, as well as with computers which have been programmed to understand MSC messages using the MSC Command Set. All MSC compatible instruments have a built-in MIDI interface and many now follow one of the various MIDI-over-Ethernet protocols.