Boss

GT-X Setup Manual page 122

Section 28 All About MIDI
Chain Cabling Scheme
The MIDI chain is the most basic MIDI configuration – and
probably the most widely used – simply because its easy
and requires no extra hardware. The basic configuration
looks like this.
Pros
1. Simple.
2. No additional hardware required other than MIDI
cables.
3. No MIDI feedback loops.
Cons
1. Failure of a single unit affects all subsequent units.
2. MIDI THRU features required on ALL mid-chain
units.
3. Long chains can cause signal loss issues and
message corruption.
Careful consideration of unit placement can alleviate
problems of MIDI THRU. But if two of the units you want
to control require MIDI THRU then you really need a star
configuration.
Ring Cabling Scheme
This is a chain that has had the last unit connected to the
first. This scheme is not recommended due to MIDI THRU
problems and the possibility of MIDI feedback loops.
However it is VERY common when using the GT-3/5
connected to a computer for an editor – here you have a ring
between the computer and the GT-3/5. However, problems
do not occur because MIDI THRU is NOT enabled on the
PC. If you use the same configuration with a sequencer that
has MIDI THRU turned on then the same problems can
occur.
Pros
1. No additional hardware required other than
MIDI cables.
© Copyright 2000-2002 Barry S. Pearce et al.
Cons
1. Failure of a single unit affects all subsequent units.
2. MIDI THRU features required on ALL units.
3. Long chains can cause signal loss issues and
message corruption.
4. MIDI feedback loops are common
To break the MIDI feedback loop means turning OFF MIDI
THRU on one of the units. This then breaks the ring and
effectively makes two (connected) chains.
Star Cabling Scheme
This is probably the BEST of all MIDI cabling schemes.
Well structured, failure of a single unit is isolated, no
problems of feedback loops. All said this is truly a great set-
up.
In the diagram below the oval represents a splitter such as
the Philip Rees V3 MIDI THRU Unit which is a very small
1->3 splitter or the V10 which is a mains powered (from a
wall socket – not a wall wart) splitter providing an
incredible 10 outputs from a single input.
Pros
1. Failure of a single unit doesn't affect any other unit
(except the splitter)
2. MIDI THRU features not required on ANY unit.
3. The splitter normally provides buffered outputs so
signal chain length is no longer an issue (cable
length however is still an issue).
4. No MIDI feedback loops.
Cons
1. Requires more hardware and money.
2. Failure of the splitter brings down the entire
system.
3. Slaved units cannot transmit MIDI to other units.
This configuration is typical of switching systems described
below. MIDI is distributed to all units from a central
controller. When used with such systems this configuration
yields phenomenal power. Quite awesome.
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