The Molten Voltage MASTER CONTROL MV-58B is a programmable MIDI pedalboard controller that stores the tempo associated with 128 programs and transmits MIDI Clock to synchronize MIDI-enabled effects. Molten Voltage describes it as a simple-to-use MIDI PedalBoard Controller that turns effects on and off and selects presets, and the owner's manual calls it a fully functional stand-alone master controller for MIDI-controlled pedalboards1. It sits at the front of a MIDI pedal setup and acts as the brain, sending program changes and clock data to the MIDI-enabled pedals connected to it.
What it does and how it is controlled
The MV-58B stores a tempo with each program, so recalling a program can also recall the timing for delay times, tremolo rates and other clock-synced effects. The side controllers are used to select the 8 programs in each of the 16 banks2. The front panel controls work as follows:
| Control | What it does |
|---|---|
| CLOCK LED | Illuminated when MIDI Clock data is being sent over the MIDI OUT jack1 |
| START Button | Starts and stops the MIDI Clock output; each press sends a corresponding MIDI Start or MIDI Stop command1 |
| Display | On startup, shows version information, flashes Program 1 and shows its tempo, then indicates Program 11 |
| TAP Button | Two functions: Tempo Control and Program Storage1 |
| SELECT Knob | Turning it increases or decreases the program number; a newly selected program flashes on the display until engaged with the START Button1 |
The tap tempo is described as precision tap tempo, with a maximum tap interval of 2.5 seconds (24 bpm) and a minimum tap interval of 0.25 seconds (240 bpm)1.
MIDI output and factory programs
The MIDI OUT jack takes a standard 5-pin DIN MIDI cable and sends MIDI data as well as Molten Voltage self-programming messages to the receiving device1. The primary MIDI channel for the Molten Voltage system is MIDI Channel 15, and all MIDI Program Change messages are sent exclusively on that channel1.
Out of the box, the unit ships with factory programs already stored: Programs 1 through 64 (b0.1 through b7.8) are set to 120 bpm, Programs 65 through 128 (b8.1 through bF.8) are set to "oLd", and the MIDI channel is 151.
Power and connections
The MV-58B runs from a separate or isolated 9 volt DC power supply with a 2.1mm, tip negative connector, drawing a minimum of 100mA, plugged into the DC9V jack1. The side controllers connect using standard 1/4-inch stereo audio cables, into four stereo input jacks labeled 1 & 2, 3 & 4, 5 & 6, and 7 & 81.
The manual specifies a separate or isolated power supply at 100mA minimum. Because of that current requirement and the tip-negative 2.1mm connector, this is not a pedal to hang off a shared daisy chain without checking the supply's capacity.
Firmware versions and program select modes
The owner's manual covers firmware version 1.4 of the documentation, but the unit's own firmware matters more for how it behaves day to day1. Version 2.06 and higher has two modes for selecting programs, Active and Passive:
- Active Mode (the default): each press of a side controller sends the corresponding MIDI Program Change instantly.
- Passive Mode: side controller buttons select a pending program, which is sent when the START Button is pressed.
In Passive Mode, version 2.06 and later also sends SysEx data that allows the SIMI display to flash the pending program name; this feature is active by default1.
Units with firmware version 2.04 and older, manufactured before 10/15/14, also send Song Select data at the same time and same value as the Program Change value. If your receiving device responds to Song Select messages, that behavior differs on newer firmware1.
Support and warranty
Molten Voltage warrants the MV-58B for two years from the date of purchase to be free from defects in materials and workmanship under normal use and service, as long as the unit is used with an approved power supply. Proof of purchase is required, and user repair attempts void the warranty. Questions go to questions@MoltenVoltage.com1.
Questions
How many programs does the Molten Voltage MASTER CONTROL MV-58B store?
The MV-58B stores 128 programs, arranged as 8 programs in each of 16 banks. The side controllers select the 8 programs within a bank, and the SELECT knob moves the program number up or down. From the factory, Programs 1 through 64 are set to 120 bpm, and Programs 65 through 128 are set to the value shown as oLd, all on MIDI Channel 15.
What MIDI channel does the MV-58B use for program changes?
The primary MIDI channel for the Molten Voltage system is MIDI Channel 15. All MIDI Program Change messages are sent exclusively on that channel, so the MIDI devices you connect to the MV-58B need to be set to receive on Channel 15.
Does the MV-58B send MIDI Clock?
Yes. The MV-58B transmits MIDI Clock over its MIDI OUT jack, and the CLOCK LED illuminates when MIDI Clock data is being sent. The START button starts and stops the clock output, sending a corresponding MIDI Start or MIDI Stop command each time.
How long is the warranty on the MV-58B?
Molten Voltage warrants the unit for two years from the date of purchase against defects in materials and workmanship under normal use and service, as long as the unit is used with an approved power supply. Proof of purchase is required, and user repair attempts void the warranty. Questions can be sent to questions@MoltenVoltage.com.
What is the tap tempo range of the MV-58B?
The MV-58B offers precision tap tempo with a maximum tap interval of 2.5 seconds, which works out to 24 bpm, and a minimum tap interval of 0.25 seconds, or 240 bpm. The TAP button also doubles as the Program Storage control.
Sources (2)
- Master_Control_MV-58B_-_PedalBoard_MIDI_Controller_and _Clock_-_Owners_Manual_by_Molten_Voltage.pdf, Molten Voltage (moltenvoltage.com), 2015
- MASTER CONTROL .:. MIDI PedalBoard Clock and Brain .:. by Molten Voltage .:. Footswitch Controller to Recall Presets, Molten Voltage
