ALM mmMIDI (2019–2025)
Two channels of MIDI-to-CV in 4HP that just works - until your DAW floods it with data and everything glitches out.
Overview
Plug in a MIDI cable, power up, and within seconds you're playing your Eurorack from a keyboard or DAW. No menus, no screens, no 20-minute calibration. The mmMIDI is a dual-channel MIDI-to-CV converter that strips out every unnecessary feature and just tracks and syncs clock. The original mkI launched in 2019 as a DIN-only unit. It lacked USB, but its immediacy won over skeptics fast. Then in 2025, ALM quietly rolled out the mkII. Same design, now with USB-C, class-compliant with tablets, phones, and laptops without drivers. No firmware update needed, no extra power draw.
The restraint is the point. Other manufacturers pack MIDI converters with arpeggiators, scales, and microtuning options. The mmMIDI does exactly two things: it converts two MIDI note channels into 1V/oct CV, velocity, and gate outputs, and it translates MIDI clock into a 24ppqn analog clock and run signal. That clock output is tailored to sync Pamela's PRO Workout, ALM's own clock module, so it pairs naturally with a rig built around Pam's timing. The only configuration is setting MIDI channels with a learn button. There are no hidden menus, and no SysEx dumps unless you're tweaking the C0 offset (more on that later). It assumes you know what you're doing and gets out of the way.
And it works - *most* of the time. Owners report near-instant response, with latency between 200 and 400 microseconds, which is tight enough for all but the most timing-sensitive patches. The 12-bit factory-calibrated CV output spans 0-8V, giving eight full octaves of tracking, and gates sit at +5V, which works with virtually every Eurorack input. The trade-off is that it accepts *all* MIDI data on its channels. A DAW like Ableton Live that sends pitch bend, aftertouch, or control changes by default can overwhelm the module, and you get double triggers, stuttering gates, or erratic clock behavior. The fix is careful MIDI filtering in your software. This isn't a hardware flaw, just a consequence of the "dumb" design. It doesn't filter, it obeys. That's fine with a clean MIDI source and a headache with a messy one.
There's also the optional mmT expander, a separate module that adds eight assignable key-triggered gate outputs. Think of it as turning your MIDI keyboard into a drum rack controller: press C1, get a kick; D1, a snare. It suits live performance, especially with a compact controller like the Keystep. It doesn't stack directly on the mmMIDI. It connects via a ribbon cable and takes another 4HP, so the full system uses more rack space than the base module.
Specifications
| Manufacturer | ALM (Busy Circuits) |
| Production Years | 2019–2025 |
| Model Variant | mkI (DIN MIDI only), mkII (DIN + USB-C) |
| Original Price | $115 USD (mkI), £170 GBP (mkII) |
| Width | 4 HP |
| Depth | 38 mm |
| Power | +12V 50mA, -12V 0mA |
| MIDI Inputs | DIN MIDI (5-pin), USB-C (mkII only) |
| CV Outputs | Dual 1V/oct (0–8V range) |
| Gate Outputs | Dual +5V gate/trigger |
| Velocity Outputs | Dual (0–8V) |
| Clock Outputs | Analog x24 clock, Run (start/stop) |
| Expander Support | mmT (8 key-mapped gate outputs) |
| MIDI Response Latency | 200–400 µs |
| CV Resolution | 12-bit (factory calibrated) |
| Firmware Updates | via SysEx over USB or DIN |
| Weight | Approx. 100g |
| Mounting | Standard Eurorack, reverse power protection |
Key Features
No-Config Operation
The mmMIDI's biggest selling point is that it needs no setup. Plug in MIDI, press the learn button, play a note to assign the channel, and you're done. No displays, no button-holding sequences, no software editors. ALM explicitly stated they have no plans to add configuration options beyond MIDI channel assignment. That means no scaling, no offset trimming from the front panel, and no filtering of extraneous MIDI data. You gain reliability and speed and give up flexibility. Users coming from complex MIDI processors like the Kenton Pro Solo or Expert Sleepers FH-2 may find it limiting. Those who just want to play a VCO from a keyboard won't miss the menus.
USB-C on the mkII
The 2025 mkII revision added USB-C MIDI support without increasing power draw or changing the form factor. You can plug it directly into an iPad running a MIDI app, a smartphone, or a laptop without a separate MIDI interface. It's class-compliant, so no drivers are needed on any major OS. The USB connection carries only data and doesn't power the module, so you still need a Eurorack power supply. Paired with a wireless MIDI controller, it can go fully cable-free, which makes the mkII a favorite for portable setups. The original mkI remains DIN-only, so check which version you're getting if you buy used.
Firmware Tweaks for Pitch Offset
One of the few configurable aspects of the mmMIDI is the MIDI note-to-CV offset, which by default maps MIDI note C0 to 0V. For users with controllers that can't play below C1, this makes the lowest octave unreachable. ALM addressed this with a firmware update (available via SysEx) that toggles the offset by ±2 octaves with a double-click on the learn button. You won't find it in the manual unless you dig into the ALM firmware page. It helps with hardware like the Arturia Keystep or Novation Launchkey, which don't transmit C0. Service technicians observe that many returns or "faulty unit" reports come from users unaware of this firmware option. Once updated, tracking issues often vanish.
Historical Context
The mmMIDI arrived in late 2019, when Eurorack modules were getting smarter, with embedded processors, color screens, and deep firmware layers. Against that, the mmMIDI went back to "one function, done well." It wasn't the first MIDI-to-CV converter, nor the most feature-rich, but it was the first to make the process genuinely *simple*. Competitors like the Doepfer MSY2 or Kenton Pro Solo offered more features - scale quantization, multiple outputs, extensive MIDI filtering - but required setup and often suffered from lag or instability. The mmMIDI didn't interpret. It translated.
As more musicians began blending DAWs with modular systems, the need for a reliable, low-latency bridge grew. The mmMIDI filled that gap, especially for users of ALM's Pamela's PRO Workout, which had become a clocking staple. The 24ppqn clock output matched Pam's internal timing standard, so sync was solid when the source was clean. The refusal to filter MIDI data also exposed a split in the modular world: software was getting more dominant, and hardware had to cope with messy MIDI streams from DAWs. The mmMIDI worked flawlessly with hardware sequencers like the Elektron Digitakt or Arturia Beatstep Pro, but stumbled with Ableton Live unless carefully configured. That limitation wasn't accidental. ALM built it for users who wanted control.
Collectibility & Value
The mmMIDI isn't rare, but it's sought after. The mkI (2019-2024) typically sells for $120-$150 used, depending on condition and whether it includes the optional MIDI-TRS adapter. The mkII (2025) commands a premium, around $170-$200, due to its USB-C capability and newer firmware. Prices on Reverb and eBay have stayed stable, with no signs of inflation, which suggests strong availability and no cult status - yet. Collectors note that original mkI units with early firmware (pre-offset fix) are sometimes discounted, since they need a SysEx update to be fully functional with modern controllers.
Common failures are few, but not nonexistent. The most reported issue is MIDI input dropout, usually traced to a failing optocoupler on the DIN input. It's a standard component and service technicians can replace it in minutes, but it's a known weak point, especially in units used frequently with unshielded cables. The USB-C port on the mkII has proven sturdy, with no widespread reports of connector failure. Power issues are rare, thanks to reverse polarity protection, but owners report occasional noise on the CV lines if the module shares a crowded power bus. Decoupling caps on the power cable often resolve this.
Always test the clock output when buying. Some users report drift when syncing to DAWs, but this is almost always MIDI jitter in the source, not the module. Test with a hardware sequencer first. Also check the firmware version, since anything before 2022 may lack the ±2 octave offset toggle. If you're buying used, ask the seller to confirm whether they've updated it. And if you're using Ableton, don't expect it to work out of the box. Route MIDI through a dedicated track with only note and clock data enabled, and disable all other MIDI outputs to the module.
Market Value
┌──────────────────────────────────────────────────────────────────────────┐ │ ALM MMMIDI Nov 2026 │ ├──────────────────────────────────────────────────────────────────────────┤ │ High $238 Latest $200 │ │ Median $200 Trend — │ │ Low $170 Volume ~1/mo │ ├──────────────────────────────────────────────────────────────────────────┤ │ $300 ┤ │ │ │ │ │ │ │ │ $214 ┤ . . │ │ │ .│ │ │. . │ │ │ │ │ $100 ┤ │ │ ├─────────────────────────────────────────────────────────────────│ │ vol │█ █ █ █ █│ │ └─────────────────────────────────────────────────────────────────│ │ 2026-01 2026-04 2026-07│ └──────────────────────────────────────────────────────────────────────────┘
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eBay Listings
Recently sold on eBay: $170–$238 (median $200, based on 5 completed sales, past 12 months)
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