The RJM Music MultiBox is a small, multi-purpose MIDI utility box: RJM Music describes it as "a multi-purpose problem solver in MIDI systems." In one unit it works as a MIDI thru box and splitter, a converter between standard 5-pin MIDI and TRS MIDI, a splitter or combiner for bidirectional MIDI connections, and a phantom power adapter for a compatible MIDI controller. It is made in the USA1.
What the MultiBox does
The box runs in four modes, each aimed at a different MIDI wiring problem on a pedalboard or in a rack2:
- MIDI Thru Box: splits one incoming MIDI signal to multiple outputs, up to three standard 5-pin MIDI outputs1
- TRS MIDI Converter: converts standard 5-pin MIDI to TRS MIDI for use with devices that require it1
- Phantom Power Adapter: combines a 5-pin MIDI connection with AC or DC power and routes them to a 7-pin MIDI connection, used to phantom power a compatible MIDI controller1
- Bidirectional MIDI Converter: splits a bidirectional MIDI connection into separate MIDI input and output jacks, or combines a MIDI input and output connection into a bidirectional MIDI connection1
As a splitter, RJM describes using it to split the output of a MIDI controller to multiple devices, both standard 5-pin MIDI and TRS MIDI1. The company also describes a rack use: putting the MultiBox with an Axe-Fx or Kemper Profiler to combine MIDI In, MIDI Out and power connections into a single 7-pin MIDI cable running to the MIDI controller2.
Jacks and MIDI connections
| Connection | Detail |
|---|---|
| MIDI input | 1 x 7-pin MIDI input, compatible with 5 or 7 pin MIDI connections2 |
| MIDI output | 1 x 5-pin MIDI output, with optional bidirectional MIDI connection to the MIDI input2 |
| MIDI thru | 1 x 5-pin MIDI thru2 |
| Configurable jack | 1 x 5-pin MIDI jack, configurable as MIDI thru or MIDI input2 |
| TRS MIDI | 4 x TRS MIDI jacks, individually configurable for Tip Active, Ring Active and Standard MIDI types2 |
The four TRS jacks being individually configurable matters in practice, because TRS MIDI devices vary in which conductor carries the signal. Being able to set each jack for Tip Active, Ring Active or Standard MIDI type lets one box serve mixed devices2.
Power
The MultiBox needs 9 to 12 volts, AC or DC with either polarity, drawing 50mA minimum, through a BOSS-type 5.5mm/2.1mm barrel connector2. It does not include a power supply; RJM says it can be powered by any standard 9 volt BOSS type power supply or a multi-output pedal power supply2.
Because the MultiBox accepts AC or DC with either polarity, it can share a pedalboard power supply, but its 50mA minimum draw should be budgeted against the supply's available current2.
B-Stock units
RJM Music also sells the MultiBox as a B-Stock unit. B-Stock units are brand new but have minor scratches or blemishes from manufacturing, and they have the same warranty as new units2. The B-Stock unit is listed at a regular price of £106.00 GBP and a sale price of £91.00 GBP on the RJM Music store12.
Where it fits in RJM's range
RJM Music is best known for MIDI foot controllers and loop switchers, including the Mastermind PBC, the smaller Mastermind PBC/6X and the Mastermind GT/10 and GT/16. The MultiBox is not a controller itself; it is the wiring utility that sits between a controller such as those and the MIDI-equipped devices it runs. For more on the wider category, see Midi Pedals.
Questions
Does the RJM MultiBox come with a power supply?
No. RJM Music states that the MultiBox does not include a power supply or AC adapter. It can be powered by any standard 9 volt BOSS type power supply or a multi-output pedal power supply, and it needs 9 to 12 volts, AC or DC with either polarity, at 50mA minimum, through a BOSS-type 5.5mm/2.1mm barrel connector.
Can the MultiBox split one MIDI signal to several devices?
Yes. In MIDI Thru Box mode the MultiBox splits one incoming MIDI signal to multiple outputs, up to three standard 5-pin MIDI outputs. RJM also describes using it as a MIDI splitter to feed the output of a MIDI controller to multiple devices, both standard 5-pin MIDI and TRS MIDI.
Can the MultiBox phantom power a MIDI controller?
Yes. In Phantom Power Adapter mode the MultiBox combines a 5-pin MIDI connection with AC or DC power and routes both to a 7-pin MIDI connection, which can phantom power a compatible MIDI controller over a single cable. RJM describes putting it in a rack with an Axe-Fx or Kemper Profiler to combine MIDI In, MIDI Out and power into one 7-pin cable.
What does B-Stock mean for the MultiBox?
B-Stock units are brand new but have minor scratches or blemishes from manufacturing, according to RJM Music. They carry the same warranty as new units. B-Stock units are listed at a regular price of £106.00 GBP and a sale price of £91.00 GBP on the RJM Music store.
Where is the RJM MultiBox made?
The MultiBox is made in the USA by RJM Music, a company known for MIDI foot controllers and loop switchers such as the Mastermind PBC and PBC/6X.
Sources (2)
- MultiBox, rjmmusic.com
- B-STOCK MultiBox, rjmmusic.com
