RXR

Comming soon 🔜.. RXR 4hp 6 Voice Drum module is paying tribute to late 80’s Japanese 🇯🇵 digital drummachines Kawai, Akai, Yamaha.. The module use a High Performance DAC with 16bit Stereo Out, offers rudimentary but effective UX with per voice editable Pitch and Decay, Panning & Level as well as built-in Compressor! The module integrate also MIDI via Bluetooth protocole 5.3 with minimum latency allowing to play drums from a DAW or any suitable mobile 📱 application! RXR saves your 6 drum-kits with all your parameters including per kit compressor's settings in memory 🧠 support merge of BT midi with physical triggers, responds to velocity midi contrôle.. Can work as standalone instrument - powered simply via USB C

Conteining arround 300 HQ drum sounds this one’s for ‘amateurs du genre’ ✌️

User Manual

MM RXR — 6-Voice PCM Drum Module

RXR — Manuel utilisateur.pdf.zip

Download ZIP • 45KB

The RXR is a 6-voice stereo PCM drum module built around a curated library of 298 drum sounds that pay tribute to late-1980s and early-1990s Japanese digital drum machines. The palette ranges from hard hits and bright cymbals to metallic percussion and classic sampled textures.

The module ships with 6 pre-configured drum kits ready to play, each with its own compressor settings and stereo mix. You can modify them, create your own combinations of sounds, and save your settings so they remain available after power-off. A factory reset is available at any time if you want to restore the original kits.

The module can also be used as a compact standalone instrument when powered over USB. It can receive Bluetooth MIDI from a computer, phone, or tablet, which makes it practical as a portable drum instrument for sketching ideas, casual playing, or use on the go.

Getting Started

Install the module in your Eurorack case and connect the supplied power cable carefully. Make sure the red stripe on the ribbon cable matches the side of the module’s power connector marked RED before powering the system.

Outside the rack, the module can also operate from USB-C power. In that use case, monitoring can be done from the 3.5 mm line/headphone output on the side of the module, while Bluetooth MIDI can be received from a computer, phone, or tablet.

Module Elements

From top to bottom, the module includes the BROWSE/EDIT rotary encoder, three status LEDs, two potentiometers for pitch and decay, stereo outputs, and six trigger inputs with associated voice LEDs. The encoder is used to navigate menus, select sounds, adjust levels, and set stereo panning.

The three status LEDs indicate Bluetooth status, active bank, and compressor status. The pitch and decay potentiometers normally apply to the selected voice, but they are reassigned to compressor parameters when the compressor edit mode is active.

First Power-Up

When the module is powered, the six green voice LEDs run through a short startup animation. During this startup window, Bluetooth MIDI can be enabled by holding the encoder, and on first boot the default drum kits are loaded automatically into memory.

The module starts on Kit 1 with the compressor enabled and is immediately ready to play.

Playing Sounds

The most direct way to play RXR is by sending trigger signals into TR1 through TR6. Each input corresponds to one drum voice, and the related green LED blinks briefly when a sound is triggered.

By default, the six inputs follow a familiar drum-kit layout: kick, snare, closed hi-hat, open hi-hat or clap, low tom or percussion, and tom, crash, or cymbal. Any voice can be reassigned to any sound available in the library.

Bluetooth MIDI can be used in parallel with the physical trigger inputs, so the module can respond to both control methods at the same time.

Navigation: How It Works

The interface is centered around the rotary encoder and organized into several modes. At any time, the blink pattern of the LEDs indicates the current mode.

BROWSE Mode

This is the default mode after startup. Turning the encoder moves between the six voices, and the selected voice LED blinks rapidly. If the encoder is left untouched for a few seconds, the blink stops to reduce distraction while playing.

Action	Duration	Effect
Short press	< 0.5 s	Enter sample edit mode for the selected voice
Double short press	two close clicks (< 0.35 s apart)	Enter compressor edit mode
Long press	~ 1 s	Enter kit select mode
Very long press	~ 3 s	Enable or disable the compressor

EDIT SAMPLE Mode

In this mode, the selected voice LED stays lit steadily. Turning the encoder browses through the sounds available in the current bank, and each sound is previewed automatically as you scroll.

Whenever a new sample is selected, its pitch resets to its natural playback speed. If you then move the Pitch potentiometer, the pitch changes from that natural value using relative tracking.

A trigger received on the selected voice while browsing plays the current previewed sound at natural pitch, which makes it easy to audition sounds in rhythm. A short press confirms the sound and moves to level editing, while a long press changes bank.

EDIT LEVEL Mode

In this mode, the selected voice LED uses a double-blink pattern. Turning the encoder adjusts the volume of the selected voice.

The Pitch and Decay pots are active here and in adjacent edit modes. They use relative tracking, so they respond to movement rather than to absolute physical position, which avoids abrupt jumps.

A short press confirms the level and moves to panning. A long press cancels and returns to BROWSE mode.

EDIT PAN Mode

In this mode, the selected voice LED uses a triple-blink pattern. Turning the encoder left or right moves the sound across the stereo field, with center sending equally to both channels.

A short press confirms panning, saves the current sound-related changes, and returns to BROWSE mode. A long press cancels the edits and restores the previous settings.

EDIT COMPRESSOR Mode

This mode is entered with a double short press from BROWSE mode. While active, the orange COM LED blinks.

Potentiometer	Role in EDIT COMPRESSOR	Range
Pitch	Compressor depth	Ratio from 2:1 to 16:1
Decay	Release time	200 ms to 2000 ms

The compressor is automatically enabled while this mode is active so you can hear adjustments in real time. A short press saves the compressor settings to the current kit, while a long press cancels the changes. If no potentiometer is touched for 15 seconds, the mode exits automatically with cancellation.

Drum Kits

RXR can store six complete drum kits. Each kit memorizes the selected sound for each voice, the bank assignment, pitch, decay, volume, stereo panning, and its own compressor settings.

Default Kits

On first startup, six kits are pre-loaded with sounds, mix, and compressor settings. They are designed to showcase the range of the module and provide immediately usable starting points covering harder, cleaner, brighter, more atmospheric, and mixed-style drum set combinations.

Each kit also includes a pre-configured stereo image based on classic drum-mix conventions, with centered kicks, near-center snares, offset hats and claps, and wider toms and cymbal-style voices. This gives the module a wider and more produced stereo presentation right away.

Loading a Kit

From BROWSE mode, a long press enters KIT SELECT mode. In this mode, the green LEDs form a horizontal bar to indicate the selected slot, while the red BANK LED blinks rapidly.

Turn the encoder to browse the six kits, then do a short press to load the displayed kit. The voices and compressor settings update immediately, and the module returns to BROWSE mode.

Saving a Kit

To save changes, enter KIT SELECT mode, choose the destination slot, and do a long press. The current kit is then written into that slot, replacing the previous contents if necessary.

RXR also performs an automatic save of small edits after three seconds of inactivity. If you switch kits before that timeout, the current kit is saved immediately before the new one is loaded.

Factory Reset

To restore the original six kits, power off the module, hold the encoder, and power it back on while keeping the encoder pressed for five seconds. After confirmation flashes, the saved kits are overwritten with the factory defaults.

If the encoder is released before the five-second point, Bluetooth is activated instead of triggering the reset.

The Compressor

RXR includes an internal compressor that ducks the other voices when the kick drum plays. This creates the pulsing sidechain-style movement commonly used in electronic music production.

A very long press from BROWSE mode enables or disables the compressor globally. The orange COM LED is lit when the compressor is active and off when disabled.

Each kit stores its own compressor state and settings, including enable/disable, depth, and release. When the compressor is disabled, the sound is more direct and louder, while a built-in soft clipper helps smooth overload when several voices play at once.

Bluetooth MIDI

RXR can receive MIDI notes wirelessly over Bluetooth Low Energy. Bluetooth is disabled by default to minimize unnecessary power use and reduce background noise.

To activate Bluetooth, hold the encoder during startup until the LEDs confirm activation with four quick flashes. Once active, the blue BT LED blinks slowly while waiting for a connection and stays solid when connected.

Bluetooth MIDI can operate at the same time as the physical trigger inputs, allowing hybrid use with sequencers, pads, mobile devices, or manual trigger sources in parallel.

Using RXR Standalone

When powered over USB-C, RXR can be used outside a Eurorack case as a compact standalone drum instrument. In this setup, Bluetooth MIDI can be received from a Mac, PC, phone, or tablet, and monitoring can be done from the side-mounted 3.5 mm line/headphone output.

This makes the module practical for portable writing sessions, quick sound design, casual jam use, or simple live sketching without a full modular system.

Bluetooth Noise

Bluetooth radio activity can introduce a slight background noise into the audio path, especially at high output levels and when no signal is present. Pairing can also be slightly slower than on more consumer-oriented Bluetooth devices because the module is configured to reduce this noise as much as possible.

MIDI Note Mapping

RXR follows the standard General MIDI percussion mapping, so most music software will assign the main drum notes automatically. The primary note assignments are as follows.

MIDI Note	Name	Triggered Voice
36	C1	Voice 1 (kick)
38	D1	Voice 2 (snare)
42	F#1	Voice 3 (closed hi-hat)
46	A#1	Voice 4 (open hi-hat / clap)
49	C#2	Voice 5 (tom / percussion)
51	D#2	Voice 6 (tom / crash / cymbal)

The module also accepts alternate percussion notes and redirects them to the most appropriate voice. It can also be played from the white keys of a standard keyboard across octaves, and it accepts MIDI on all channels.

LED Indicators — Visual Summary

The LEDs continuously indicate system state. The selected voice LED changes its blink pattern depending on the active mode.

Mode	Behavior of the selected voice LED
BROWSE	Steady rapid blink
EDIT SAMPLE	Lit steady, no blinking
EDIT LEVEL	Double blink
EDIT PAN	Triple blink
KIT SELECT	Horizontal bar
EDIT COMPRESSOR	Voice LEDs neutral; orange COM LED blinks

LED	Color	Behavior
BT	Blue	Off if Bluetooth is disabled; slow blink while waiting; steady when connected
BANK	Red	Indicates current bank by blink count; rapid blink in KIT SELECT
COM	Orange	Lit when compressor is enabled; off when disabled; blinks in EDIT COMPRESSOR

Command Cheat Sheet

From BROWSE	Effect
Turn encoder	Navigate between voices
Short press	Enter EDIT SAMPLE
Double short press	Enter EDIT COMPRESSOR
Long press (~ 1 s)	Enter KIT SELECT
Very long press (~ 3 s)	Enable/disable compressor

From EDIT SAMPLE	Effect
Turn encoder	Browse sounds in the bank
Trigger input	Play current preview sound
Short press	Confirm and go to EDIT LEVEL
Long press	Change bank

From EDIT LEVEL	Effect
Turn encoder	Adjust volume
Pitch pot	Adjust pitch (relative tracking)
Decay pot	Adjust decay (relative tracking)
Short press	Confirm and go to EDIT PAN
Long press	Cancel and return to BROWSE

From EDIT PAN	Effect
Turn encoder	Adjust panning
Short press	Confirm and return to BROWSE
Long press	Cancel and return to BROWSE

From EDIT COMPRESSOR	Effect
Pitch pot	Adjust depth (ratio)
Decay pot	Adjust release
Short press	Save and return to BROWSE
Long press	Cancel and return to BROWSE
15 s of inactivity	Automatic cancellation

From KIT SELECT	Effect
Turn encoder	Browse the 6 kits
Short press	Load selected kit
Long press	Save current kit into this slot

Hold encoder during boot	Effect
0–2 s (during animation)	Activate Bluetooth (4 fast flashes confirm)
5 s (held throughout)	Factory Reset of all 6 kits

Technical Specifications

Characteristic	Value
Power supply	USB-C 5V or Eurorack ±12V bus
Audio output	Stereo, PCM5102 32-bit DAC
Sample rate	44100 Hz
Sound encoding	16-bit native for kicks, snares, and toms; 12-bit packed dithered for cymbals, hats, and percussion
Polyphony	6 simultaneous voices
Sound library	4 banks, 298 sounds total
Kit slots	6, each with its own compressor settings and stereo mix
Compressor	Internal sidechain ducking, depth and release adjustable
Wireless connectivity	Bluetooth Low Energy MIDI

Output Level Note

RXR was originally designed around line-level use. The additional gain needed to reach typical modular-level output also raises the background noise floor, so for more delicate applications such as recording it is recommended to lower the output level to the point where the added noise is no longer intrusive.

Updating the Firmware

Firmware updates can be installed over USB-C with a computer and a compatible Chromium-based browser using Espressif’s web flashing tool. The update process writes one or more .bin files to the module after it is placed into programming mode with the BOOT and RESET buttons on the board.

In brief, connect the module, enter programming mode by holding BOOT while briefly pressing RESET, open web.esptool.io, select the correct serial port, load the firmware file or files at the required addresses, then program the device and reboot it. Saved kits are normally preserved unless the firmware changes the kit format.

Always use firmware files specifically provided for RXR. Flashing firmware intended for another device can make the module unusable until it is reprogrammed correctly.

Troubleshooting

If no sound is heard, verify the audio connection and monitoring level. If triggers do not react, verify the trigger cables and input voltage. If Bluetooth will not connect, make sure it was enabled during startup. If the module does not power on, try another USB-C cable or power source.

If a noise or hiss appears on only one output while using the module in Eurorack, the cause is likely a ground loop between USB power and the Eurorack bus. In that case, power the module from only one source at a time: USB alone or Eurorack alone.

If a kit behaves incorrectly after a firmware update, perform a factory reset by holding the encoder for five seconds at startup. This restores the default kits and returns the module to a known working state.