SBXAPC – APC Mini Soundboard

A simple, standalone Windows soundboard that turns an Akai Professional APC Mini (original V1 or MK2) into a 64-pad sample player. No Ableton or DAW required.

Features

• 64 pads → 64 independent sample slots (polyphony allowed)
• Load WAV / MP3 / FLAC / OGG (and other formats NAudio supports) per pad
• Record from the default microphone straight onto a pad
• Instant playback from the hardware or the on-screen grid
• Save / Load portable setups (setup.json + samples/)
• Auto-save last session on exit, auto-load on next start
• LED feedback using the classic Ableton-mode colors (works on V1 and MK2)
• 9 faders for column + master volume
• Round buttons + Shift for stop/mute-style control

Requirements

• Windows 10/11
• .NET 8 Desktop Runtime (or SDK to build)
• APC Mini in Ableton Live mode (USB)

Portable executable (thumb-drive ready)

A self-contained single-file build needs no .NET install on the target PC:

cd SBXAPC
dotnet publish SBXAPC -c Release -r win-x64 --self-contained true ^
  -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true

Output:

SBXAPC\bin\Release\net8.0-windows\win-x64\publish\SBXAPC.exe

Copy that folder (or just SBXAPC.exe) anywhere — USB stick, laptop, etc. Session data and recordings are stored in a Data\ folder next to the exe.

Build & Run (development)

cd SBXAPC
dotnet restore
dotnet build -c Release
dotnet run --project SBXAPC -c Release

Or open SBXAPC.sln in Visual Studio 2022+ and press F5.

Hardware map

Control	MIDI	Action
8×8 pads	Notes 0x00–0x3F (bottom-left → top-right)	Play / stop sample
Bottom round buttons	Notes 0x40–0x47	Stop all samples in that column
Scene Launch (right)	Notes 0x52–0x59 or 0x70–0x77	Stop all samples in that row
Shift	Note 0x62 (98)	Modifier
Shift + pad		Stop that pad immediately
Shift + any round button		Stop everything
Faders 1–8	CC 48–55	Volume for vertical columns 1–8
Master fader	CC 56	Overall output volume

LED colors (common V1 / MK2 subset)

State	LED
Empty	Off
Loaded	Green
Playing	Yellow / amber
Recording	Red blink

UI

• On-screen 8×8 grid mirrors the controller (top of window = top row of pads)
• Left-click pad → play / stop (same as hardware)
• Right-click pad → Load Sample… / Record / Clear / Stop
• Load Setup… / Save Setup… / New / Stop All / Clear Board
• Keyboard: Ctrl+O load, Ctrl+S save, Ctrl+N new, Esc stop all (or finish recording)

Setup folder format

MySetup/
  setup.json
  samples/
    00_kick.wav
    03_snare.mp3
    ...

setup.json maps pad index → relative sample path and stores master/column volumes. Copy the whole folder to move a setup between PCs.

Last session is stored under:

%LocalAppData%\SBXAPC\LastSession\

Tips

1. Plug in the APC Mini before or after launching — the app polls for it every 1.5s.
2. If LEDs or notes seem wrong, hold the APC Mini’s mode button so it is in Ableton Live mode (not Alternate/Note mode).
3. Second press of a playing pad stops that sample.
4. Empty pads stay dark and do nothing.

Tech

• C# / .NET 8 WinForms
• NAudio – playback + mic recording
• Melanchall.DryWetMidi – MIDI I/O

License

Use freely for personal/live performance projects.