The RJM Mastermind LT is a MIDI foot controller made by RJM Music Technology, announced in January 2017 as "a low-cost, yet very capable, MIDI foot controller" in the company's Mastermind line1. It puts seven footswitches, a large LCD display, and an expression pedal input in a compact floor unit, and it is aimed at players who run MIDI-equipped effects, amp channels, or rack gear and want preset and song control from the floor without the size or price of the larger Mastermind GT controllers21.
RJM describes the Mastermind LT as carrying "all of the MIDI capabilities and vast configurability of the Mastermind GT" in a smaller package2. Ron Menelli, founder and engineer of RJM Music's products, said at launch that the core of the unit, the processor, memory and USB interfaces, "remains the same as those on RJM's more expensive products"1.
Buttons, presets and the display
The LT has seven buttons, each with a multi-color LED, and RJM says the buttons are "completely user configurable for color and function"2. That means you decide what each switch sends and what color it shows, so the layout can match your rig rather than a fixed template.
Beyond the seven physical switches, the controller organizes its capacity like this2:
- 768 presets for storing your sounds and settings
- 16 button pages that can be set up to perform different functions and control multiple devices
- 16 connected devices it can address at once
- A large main LCD display showing the preset number, preset name and/or song name
The 16 button pages are the main way the LT stretches its seven switches: a page can hold a different set of assignments, so one page might switch amp channels while another sends individual program changes to your effects2.
Power and connections
The Mastermind LT runs from 9-12VDC at 150mA through a 2.1mm ID / 5.5mm OD barrel connector, and RJM notes it accepts either center positive or center negative polarity2. It can also be bus powered from a USB port when connected to a PC or Mac2.
The LT's phantom power capability lets it run with a single MIDI cable and no separate power supply, but only if the MIDI device at the other end supplies phantom power. Otherwise, use the barrel connector or USB bus power2.
Its jacks cover the rest of a stage rig2:
| Connection | What it does |
|---|---|
| Expression pedal input | Sends continuous control MIDI messages to your effect devices |
| External switch input | 1 TRS jack for a total of 2 switches; momentary switches required |
| Function switch output | 1 TRS jack for a total of 2 switches; electrically isolated |
| MIDI | Phantom power capability allows running with a single MIDI cable, no separate power supply needed |
| USB | Direct connection to a PC or Mac; can be bus powered from the USB port |
The expression pedal input can generate MIDI continuous controller messages to control parameters on your MIDI devices21, which pairs naturally with an expression pedal you may already own. The external and function switch jacks let you add momentary switches for extra control or send switch signals out to other gear.
Where it came from
The Mastermind LT is RJM Music Technology's compact MIDI foot controller, built around the same core design as the rest of the Mastermind line but in a smaller footprint: it runs on 9-12VDC at 150mA with a center positive or negative 2.1mm ID / 5.5mm OD barrel connector, measures 11.5 (W) x 5.0 (D) x 2.75 (H) inches, and weighs 1.9lb2. Reviewers have taken to that smaller size. Guitar World's reviewer wrote, "But if you want a switcher with a smaller footprint, the easy-to-use LT is a high-quality and highly creative tool."3
What reviewers said
Premier Guitar reviewed the Mastermind LT in August 2021 and came away positive, with one reservation about price relative to its feature set. The review called it "a high-quality and highly creative tool" for players who want a smaller footprint, while noting it is "slightly expensive given the lack of a loop switcher overall"3. The reviewer found it high quality and easy to navigate3.
"But if you want a switcher with a smaller footprint, the easy-to-use LT is a high-quality and highly creative tool."
That distinction matters when comparing it within RJM's own range: the Mastermind LT is a controller only, while the Mastermind PBC line combines MIDI control with audio loop switching on the same floorboard. If your effects are all MIDI-capable, the LT covers preset and parameter control in a smaller, lighter unit21.
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Questions
How many presets does the RJM Mastermind LT hold?
The Mastermind LT holds 768 presets, according to RJM Music Technology. It also offers 16 pages of buttons, which can be set up to perform different functions and control multiple devices, and it can work with up to 16 connected MIDI devices. A large main LCD display shows the preset number, the preset name, or a song name.
Can the Mastermind LT run on MIDI phantom power?
Yes. RJM Music Technology says the Mastermind LT has phantom power capability, which lets you run the controller with a single MIDI cable and no separate power supply. If your MIDI device can supply phantom power, the LT draws what it needs down the MIDI cable. It can also be powered conventionally or bus powered over USB.
Does the Mastermind LT take an expression pedal?
Yes. The Mastermind LT has an expression pedal input that can generate MIDI continuous controller messages. That lets a connected expression pedal send continuous control MIDI messages to your effect devices, so you can sweep parameters like delay time, reverb mix, or amp volume with your foot.
Can you connect more than one Mastermind LT together?
Yes. RJM Music Technology states that more than one Mastermind LT can be connected together and used in multiple locations on stage. That makes it possible to keep one controller at your main position and another elsewhere on the stage, both working with the same MIDI rig.
Where is the RJM Mastermind LT made?
RJM Music Technology lists the Mastermind LT as made in the USA. The company was founded by Ron Menelli, who announced the Mastermind LT in January 2017 as a low-cost but very capable MIDI foot controller in the Mastermind line.
What is the warranty on the Mastermind LT?
RJM Music Technology gives the Mastermind LT a 3 year limited warranty, according to the company's product page. That covers the controller itself; for details of what the limited warranty includes, the maker's own warranty terms are the place to look.
Sources (3)
- RJM Music Unveils the Mastermind LT, Premier Guitar, 2017-01-31
- Mastermind LT, RJM Music Technology
- Quick Hit: RJM Mastermind LT Review, Premier Guitar, 2017-12-07
