AKAI APC40 mkII

Sources

• manufacturer APC40 Mk2 Communications Protocol v1.2 (AKAI Professional, 19 Jan 2015)official. 'The unit defaults to Mode 0 (Generic) on startup'. Inbound: clip launch 1–40 = notes 0x00–0x27, record arm 0x30, solo 0x31, activator 0x32, clip stop 0x34 (all four on channels 0–7 = tracks 1–8), device left / right 0x3A / 0x3B, bank left / right 0x3C / 0x3D, device on/off 0x3E, device lock 0x3F, clip/device view 0x40, detail view 0x41, crossfader A|B 0x42 (channels 0–7), stop all clips 0x51, scene launch 0x52–0x56, pan 0x57, sends 0x58, user 0x59, metronome 0x5A, play 0x5B, record 0x5D, up 0x5E, down 0x5F, right 0x60, left 0x61, shift 0x62, tap tempo 0x63, nudge − / + 0x64 / 0x65, session record 0x66, bank 0x67; track fader CC 0x07 (channels 0–7), master 0x0E, crossfader 0x0F, device knobs 0x10–0x17 (channel = selected track, Generic mode), track knobs 0x30–0x37, footswitch 0x40 (127 / 0); relative (cue 0x2F, tempo 0x0D): 1–63 up, 127–64 down; LEDs: note-on, velocity = state, RGB LEDs take the lighting type on the channel (0 = primary colour) and a palette index in velocity (3 white, 5 red, 21 green, 37 #00A9FF); channels are written 0–15 and are 1–16 here
• manufacturer APC40 mkII User Guide v1.0 (AKAI Professional)official. 'Features' top view (the faceplate here follows its numbered figure): 8 assignable knobs over the 8×5 clip grid with the five scene launch buttons at its right, clip stop and track selector rows, the per-track [number][A|B] and [S][●] buttons, nine faders with the crossfader at the bottom right, the 4×2 device knobs and button block, the cursor, Shift and Bank, the Pan / Sends / User column, Play / Record / Session, Metronome, Tap Tempo, Nudge, the tempo and cue knobs, a footswitch input
• community TouchDesigner – AKAI APC 40 MKii (NiDerLander, non-official)community. Confirms that in Generic mode the track selector buttons send no CC of their own but the device knobs' values instead, and that every other control is mapped from the protocol document
• community APC40 mk2 clip grid, Lightjams forum (non-official)community. A user reports the clip launch grid and the scene launch buttons arriving on MIDI channel 1 (the grid as 40 contiguous notes); it says nothing about which row is which

Notes

Models Generic mode (Mode 0), the one the unit starts in; Ableton Live software switches it to Ableton Live mode with a SysEx the element does not send, and then the controls change channels and the device knobs stop being banked. Channels: the protocol writes 0–15, this file 1–16. Track-strip buttons (clip stop, solo, record arm, activator, A|B) and the track faders are one channel per track, 1 to 8. In Generic mode the device knobs and device buttons are banked by the track selector: they send on channel 1 with track 1 selected, 2 with track 2 … 9 with Master, and pressing a track selector re-sends the eight device knob values on that channel. The track selectors themselves send no note in Generic mode (the manual calls them radio buttons that only choose the bank), so they are drawn, not mapped; this file shows the track-1 bank. The manual's Generic-mode section calls activator, solo, record arm, pan, sends, user and the device / bank arrows 'toggle' buttons; its inbound section reports every button as note-on when pressed and note-off when released, which is what is modelled. The 40 clip pads are flagged: the manual numbers them Clip Launch 1–40 = notes 0–39 but gives no figure of which pad is which; Akai's other grids and the Ableton Remote Script count from the bottom-left, left to right, upward, and that is how they are placed (note 0 bottom-left, note 39 top-right); learn rebinds. The master fader, crossfader, cue, tempo, footswitch and track knobs list no channel in the manual: channel 1 (Lightjams reports the grid and scene buttons on channel 1 as well). The ring LEDs around the 16 knobs are written with the knob's own CC (the value) and a ring-type CC (0x18–0x1F device, 0x38–0x3F track: 0 off, 1 single, 2 volume, 3 pan) and are not modelled as LEDs. The manual also lists a 'STOP' note (0x5C) that the faceplate has no button for. LED feedback: clip pads light #00A9FF (palette 37) and scene launch buttons green (21) with the primary-colour lighting type (channel 1); single-colour buttons take velocity 1 for on. The crossfader is horizontal on the unit and drawn upright here.

Port names it recognises

matches

/apc\s*40\s*(mk\s*2|mk\s*ii|ii|2)\b/i

Signals

Every control publishes midi/apc40mk2/<control> (0..1), plus /raw; pads add /hit, encoders /delta, keys /on /off and n<note>; the last control touched is midi/apc40mk2/last.