Leprecon LP-1600 Series - Manual (Page 54)

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or by typing in a group of specific commands. Such a setup allows a complete
lighting show to be recorded and then played back flawlessly each time, synced
perfectly to the music. With a SMPTE-to-MIDI interface or a MIDI-tape sync
unit, the LP1600 can be even synchronized to tape recorded music, video, or
any type of recorded program. It is through the MIDI System Interface - the In
and Out jacks on the LP1600’s rear panel - that the console can communicate
with any other MIDI device.
8.3. Controlling the LP-1600 from a sequencer
Nearly every control on the LP1600’s front panel can be mimicked by a specific
MIDI command. Whenever a fader is moved or a button is pressed, the LP1600
will send out a corresponding MIDI message. Likewise, when another device
sends such a command to the console, it will produce the same effect as if that
control were physically moved. It is this concept that allows the LP1600 to be
controlled from a sequencer.
A MIDI sequencer is simply a device that records a stream of MIDI data, and
then plays it back exactly as it was recorded. To be more useful, most
sequencers have editing functions so that the data can be changed in helpful
ways, such as correcting errors, or raising the volume of a specific musical
passage. But mainly, the sequencer records MIDI data, and it doesn’t care
what that data is - it could be a command for a keyboard to play a note, it
could be a command to set a digital reverb to a certain program, or it could be a
command that mimics the LP1600’s GO button. Some keyboards have built-in
sequencers, other sequencers are available as stand-alone units from several
manufacturers, and there are many sequencers that are just software packages
for personal computers equipped with MIDI interfaces. Keyboard-based and
stand-alone sequencers are generally the most road-worthy, while software
sequencers usually offer the greatest flexibility in editing and the greatest
memory capacity.
In many ways, a sequencer operates like a multi-track tape recorder. There are
multiple tracks, and each track is used to record a specific instrument, each on
its own MIDI channel. To automate the LP1600, it should be recorded as one
of these “instruments” on its own track. So data has to be sent first from the
console to the sequencer to be recorded, and then from the sequencer to the
console for playback. The MIDI System Out of the LP1600, therefore, needs to
be connected to the MIDI In of the sequencer, and the sequencer’s MIDI Out
needs to be connected to the LP1600’s MIDI In. The track needs to be set to
the same MIDI channel that the LP1600’s MIDI Out is set to (see page ?___?) in
order to record data. Similarly, to play back the light cues, the LP1600 must
be receiving on the same channel (MIDI In) that the track is set to. At first, it is
simplest to set both the LP1600’s MIDI System In and Out to the same
channel.
Most MIDI devices only have one output, yet a sequencer might be driving six
keyboards, a drum machine, some effects processors, and the lighting console.
To connect all these devices to the one MIDI Out requires a MIDI Thru box -