Control Assigns - Boss

GT-X Setup Manual

MMC Play/Stop
This is short for 'MIDI Machine Control'. With this setting
you can use an EXP or CTL pedal to start and stop units
with a 'MMC IN' connection, like tape decks, multi-track
recorders and sequencers using MIDI.

Control Assigns

Using the control assign functions on the GT-3/5, you can
do further MIDI magic – they allow you to have real-time
control over the various effects and their parameters from
another unit, and in the case of the GT-5 allow you to signal
start/stop to another unit.
Target
There are two additional control assign targets on the GT-5.
These both allow you to signal a start and stop to control
another MIDI based unit.
MIDI Start/Stop & MMC Play/Stop
These are both toggled parameters. In other words they are
either ON or OFF, and thus behave in the same way as other
toggled parameters do (explained in section 23 Control
Assigns).
Using either of these as the target allows you to determine
when MIDI start/stop or MMC play/stop are sent on the
MIDI OUT connector.
You could use these to tell a sequencer to start/stop
playback of a sequenced synth part, or a drum machine to
start/stop. Which one you use would be dependent on the
receiving device.
Source
Being able to select a MIDI source is an extremely rich and
versatile way of controlling your GT-3/5 in real-time from
another unit. Indeed complete automation of real-time
parameter changes is possible. Both the GT-3 & GT-5 share
the ability to react to MIDI CC messages, and the GT-5 can
further recognised an act upon MIDI Velocity and Pitch
Bend messages. Lets take a look at each of these
possibilities.
MIDI CC#01-31, 64-95: Definitely the most useful of all
of the MIDI extensions to the control assigns. The :::::
MIDI Velo: The velocity of the MIDI Note is used as the
source value. This could be used by a sequencer to control
individual parameters of the GT-5. However, looking at
both the official manual and the MIDI implementation
document, it looks like ANY MIDI Note on message will be
used as the source rather than a specific note. This lessens
the usability as you effectively have a single control source
for the values. Use of MIDI CC is preferable to this.
© Copyright 2000-2002 Barry S. Pearce et al.
Section 28
MIDI P.B: A pitch bend message is used to as the source
for the control assign. This means the modulation wheel
from a synth can be used to directly control a real-time
parameter of the GT-5. However Pitch Bend only provides
a single source of information (whereas CC has many
sources depending on the CC number) and thus the use of
Pitch Bend messages may be limited in practice.
This ability to control the GT-3/5 in real-time is extremely
useful for synchronisation of effects in the live environment.
It can also allow you to expand your system, and
particularly on the GT-3 allows you to overcome the
limitation of ONE external expression pedal OR external
footswitches. For instance I own a Digitech MC
expression pedal that transmits the pedal position as a MIDI
CC message. This is allows me to use my GT-3 with two
expression pedals AND two external footswitches. The
need may not be so pressing for the GT-5 but you can see
the possibilities – especially if you use an expression pedal
on an external foot controller.
Internal Pedal Trigger
The Internal Pedal (I-PDL) was discussed in section 23
Control Assigns. Both the GT-3 & GT-5 can trigger the I-
PDL based on the value of a CC message, and additionally
the GT-5 can trigger the I-PDL from a MIDI Velocity or
Pitch Bend message. Lets take a quick look at each.
MIDI CC#01-31, 64-95: Activates the trigger when the
value of a MIDI Control Change Message from an external
MIDI device exceeds the middle value.
MIDI Velo: Activates the trigger when the value of a MIDI
Velocity Message received from an external MIDI device
exceeds the median value. This could a message from a
synth's velocity sensitive keyboard. Examining both the
official manual and the MIDI implementation document, it
would appear that ANY MIDI Velocity message (note on
messages) and thus ANY NOTE which has a velocity >
than the median value will trigger the I-PDL. Once again
use MIDI CC messages in preference.
MIDI P.B: Activates the trigger when the value of a MIDI
Pitch Bend Message from an external MIDI device exceeds
the middle value. This could a message from a Synth's
Velocity Mod wheel. This is probably more useful than the
above setting. Again, remember that Pitch Bend only
provides a single source of information (whereas CC has
many sources depending on the CC number) and thus the
use of Pitch Bend messages may be limited in practice.
What this allows us to do is to set up a synth or other device
to trigger an effect such as fade in/fade out (or whatever
your imagination has come up with!) on the GT-3/5. Once
again, this is extremely useful for synchronisation of effects
in the live environment.
All About MIDI
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MIDI
127