| name | midi-rekordbox |
| description | Use when parsing or generating Rekordbox MIDI Learn CSV mapping files, implementing MIDI-to-function lookup, working with deck channel offsets, hi-res 14-bit CC controls, or understanding DDJ/XDJ/DJM controller MIDI conventions. |
Rekordbox MIDI Learn CSV Protocol
Reverse-engineered from bundled controller CSVs and the official AlphaTheta MIDI Learn Operation Guide. The guide documents the UI workflow; this skill documents the CSV wire format that the UI reads and writes.
Ground truth: references/DDJ-FLX10.midi.csv (567 lines, 4-deck) and references/DDJ-GRV6.midi.csv (339 lines, 2-deck).
File Structure
Line 1: @file,1,DDJ-FLX10 ← file marker, format version (always 1), controller name
Line 2: #name,function,type,input,deck1,deck2,deck3,deck4,output,deck1,deck2,deck3,deck4,option,comment
Line 3+: data rows, section headers, or empty separators
The CSV is also the EXPORT/IMPORT format — Rekordbox's MIDI setting window reads and writes this exact structure.
Column Definitions (15 columns, 0-indexed)
| Col | Header | Purpose | Notes |
|---|
| 0 | #name | Internal identifier | Often matches col 1; # prefix = not user-assignable in MIDI Learn UI |
| 1 | function | Rekordbox function (key column) | Supports modifiers: +Shift, +LongPress, +Press |
| 2 | type | Control type | See Control Types below |
| 3 | input | Base MIDI IN code (4-digit hex) | Empty when deck columns have full codes |
| 4-7 | deck1-deck4 | Input deck assignments | Channel offsets OR full MIDI codes |
| 8 | output | Base MIDI OUT code (LED feedback) | Often mirrors input |
| 9-12 | deck1-deck4 | Output deck assignments | Mirrors input pattern |
| 13 | option | Flags (semicolon-separated) | See Options below |
| 14 | comment | Human description | |
MIDI Hex Format
Codes are 4-digit hex: SSDD — status byte + data byte.
Status byte = upper nibble (message type) + lower nibble (channel 0-15)
9x = Note On Example: 900B = Note On, Ch 0, Note 0x0B
8x = Note Off Example: 800B = Note Off, Ch 0, Note 0x0B
Bx = Control Change Example: B640 = CC, Ch 6, CC 0x40
Channels are 0-indexed in the CSV (0-15) but conventionally displayed as 1-16.
Deck Assignment Patterns
Pattern 1: Base Code + Channel Offsets (most common)
PlayPause,PlayPause,Button,900B,0,1,2,3,900B,0,1,2,3,Fast;Priority=50;Dual,Play/Pause
Base 900B (Ch 0) + offsets 0,1,2,3 → Ch 0 (Deck 1), Ch 1 (Deck 2), Ch 2 (Deck 3), Ch 3 (Deck 4).
Pattern 2: Empty Base + Full MIDI in Deck Columns
Load,Load,Button,,9646,9647,9648,9649,,,,,,,Load to Deck
Input column empty; each deck column has a complete 4-digit MIDI code.
Pattern 3: Global (No Deck Assignment)
Browse,Browse,Rotary,B640,,,,,,,,,,,Browse
Channel 6 = global controls. All deck columns empty.
Pattern 4: Non-Sequential Channel Offsets
PAD1_PadMode1,PAD1_PadMode1,Pad,9000,7,9,11,13,...
Offsets 7, 9, 11, 13 → Channels 7, 9, 11, 13 for decks 1-4. Not always sequential.
Pattern 5: Multi-Row Per Function
FXPartSelectVocalOn,,Button,9714,,,,,9714,,,,,,FX PART SELECT VOCAL
FXPartSelectVocalOn,,Button,9914,,,,,9914,,,,,,FX PART SELECT VOCAL
FXPartSelectVocalOn,,Button,9B14,,,,,9B14,,,,,,FX PART SELECT VOCAL
Same function on separate rows with different MIDI codes (channels 7, 9, 11). Deck columns empty; channel is baked into the code.
Control Types
Verified in CSVs
| CSV Name | MIDI Message | Resolution | Description |
|---|
Button | Note On/Off | — | Momentary button |
Pad | Note On (velocity) | — | Velocity-sensitive pad |
KnobSliderHiRes | CC (14-bit) | 0-16383 | High-resolution fader (MSB+LSB) |
Rotary | CC (relative) | — | Rotary encoder (64=center, >64=CW, <64=CCW) |
JogRotate | CC | — | Jog wheel rotation |
JogTouch | Note On/Off | — | Jog wheel touch detect |
JogIndicator | — | — | Jog display feedback (output only) |
Difference | CC | — | Position difference (search/seek) |
Indicator | — | — | Output-only LED feedback |
Value | CC | — | Special: Needle Search or Velocity Sampler |
Parameter | — | — | Internal config, uses FFFx codes (outside standard MIDI) |
Listed in Official Guide but NOT Found in CSVs
| UI Name | Expected CSV Name | Status |
|---|
Knob/Slider (0h-7Fh) | Knob or KnobSlider | Not observed in DDJ-FLX10 or DDJ-GRV6 CSVs |
All faders in both CSVs use KnobSliderHiRes (14-bit). 7-bit knob types may exist in other controllers.
14-Bit Hi-Res Controls (MSB/LSB)
KnobSliderHiRes uses standard MIDI 14-bit CC encoding:
- MSB: CC 0-31 (coarse value, appears in the CSV)
- LSB: CC 32-63 (fine value, implicit — CC number = MSB CC + 32)
- Combined value:
MSB * 128 + LSB (range 0-16383)
Example: TempoSlider mapped to B000 (CC 0). The device also sends CC 32 as the LSB — this is NOT in the CSV but must be handled by any parser.
CSV entry: B000 → CC 0 on base channel (MSB)
Implicit LSB: B020 → CC 32 on same channel (LSB, not in CSV)
Parser must: recognize CC 32-63 as LSBs for CC 0-31 when the MSB maps to a KnobSliderHiRes function. The LSB shares the same function name and deck assignment.
Options Field
Semicolon-separated in column 13. Example: Fast;Priority=50;Dual
| Option | Format | Description |
|---|
Fast | flag | Priority processing for time-critical controls |
Priority=N | key=value | Priority level 0-100 |
Dual | flag | 4-deck mode support (DDJ-FLX10) |
Blink=N | key=value | LED blink rate in milliseconds |
RO | flag | Read-only: controller reports state, not user-assignable |
Value=N | key=value | Config value (used with Parameter type) |
Min=N | key=value | Minimum value |
Max=N | key=value | Maximum value |
Row Types
| Type | Column 0 | Column 1 | Example |
|---|
| Functional | name | function | PlayPause,PlayPause,Button,900B,... |
| Section header | # Name | empty | # Browser,,,,,,,,,,,,,, |
| Separator | empty | empty | ,,,,,,,,,,,,,, |
#-prefixed functional | #Name | function | #JogScratch,JogScratch,JogRotate,... |
# placeholder | # | function | #,Browse+Press+Shift,Button,... |
#-Prefixed Rows
Column 0 starting with # marks controls not assignable through the MIDI Learn UI. Two subcategories observed:
-
Hardwired + RO — Controller-reported state, firmware-fixed. All jog controls, deck select indicators. Always have RO option. (e.g., #JogScratch, #Deck3)
-
Hardwired, not RO — Real input controls with fixed MIDI assignments that can't be remapped. No RO flag. (e.g., #CrossFader with Fast, #ChannelFader)
These rows have valid MIDI codes and produce real messages. A sniffer/parser should handle them.
Special Sections
# State — Status synchronization
VinylState,VinylState,Button,903A,0,1,2,3,,,,,,RO,LED State of Vinyl buttons
DeckState,DeckState,Button,903C,0,1,2,3,,,,,,RO,LED State of DECK
# illumination — LED control (Channel 15)
LoadedIndicator,LoadedIndicator,Indicator,,,,,,,9F00,9F01,9F02,9F03,RO;Priority=100,Load illumination
JogBrightnessSetting,JogBrightnessSetting,Value,BF46,,,,,BF46,,,,,RO;Priority=100,JOG RING brightness
Uses 9Fxx (Note On Ch 15) and BFxx (CC Ch 15).
# Parameter — Internal config
JogIndicatorInterval,JogIndicatorInterval,Parameter,FFF1,,,,,,,,,,Value=12,
MidiOutInterval,MidiOutInterval,Parameter,FFF3,,,,,,,,,,Value=2,
FFFx codes are outside standard MIDI range — internal to Rekordbox.
Channel Conventions (Hardware-Specific)
Some controls are NOT in the CSV — they're hardwired in controller firmware. These channel assignments are observed empirically:
| Controller Family | Channel | Known Controls |
|---|
| DDJ controllers | Ch 6 | MicLevel (CC 5), MasterLevel (CC 8), BoothLevel (CC 9), CueMasterMix (CC 12), HeadphonesLevel (CC 13) |
| XDJ all-in-ones | Ch 4 | MasterLevel (CC 24), BoothLevel (CC 25) |
| DJM mixers | Ch 0 | MasterLevel (CC 24), BoothLevel (CC 25) |
| All (illumination) | Ch 15 | LED feedback (9Fxx, BFxx) |
Note: DDJ Ch 6 mappings confirmed on DDJ-GRV6 only. XDJ/DJM mappings are unverified — derived from community reports.
Lookup Algorithm
To find a Rekordbox function from a received MIDI message:
1. Parse message: type (note_on/note_off/cc), channel, data1
2. Build key: "{type}:{channel}:{data1}"
3. Search CSV rows:
a. Pattern 1: base_code channel + deck_offset == message channel?
b. Pattern 2: deck column contains full MIDI code matching message?
4. If CC 32-63 and no direct match:
→ Check CC (data1 - 32) as MSB for KnobSliderHiRes — this is the LSB
5. Return function from column 1, control type from column 2
Verification Status
| Claim | Evidence | Confidence |
|---|
| CSV structure (15 cols, @file header) | 2 CSVs + official IMPORT/EXPORT | High |
| Deck offset patterns 1-4 | Verified in both CSVs | High |
| Pattern 5 (multi-row) | DDJ-GRV6 lines 223-226 | High |
| Control types (verified list) | Exhaustive grep of both CSVs | High |
Knob/KnobSlider types | NOT found in either CSV | Unverified |
| 14-bit MSB/LSB | Working parser + MIDI spec | High |
# prefix = not UI-assignable | Observed behavior, not confirmed | Medium |
| DDJ Ch 6 built-in controls | Confirmed on DDJ-GRV6 hardware | Medium |
| XDJ/DJM channel conventions | Community reports, no hardware test | Low |
Sources
- Ground truth CSVs:
references/DDJ-FLX10.midi.csv, references/DDJ-GRV6.midi.csv (bundled with this skill)
- Official guide: AlphaTheta "MIDI LEARN Operation Guide" for rekordbox 7.0.5 (UI workflow, control type definitions)
- CSV source:
/Applications/rekordbox 7/rekordbox.app/Contents/Resources/MidiMappings/
- MIDI spec: https://www.midi.org/specifications (14-bit CC, status bytes)
