Switching Mixer for Disting NT

A CV/MIDI-controlled and i2c-mappable switching mixer algorithm for the Expert Sleepers Disting NT.

Overview

           ┌─────────────────────┐
Input A ──►│                     │
Input B ──►│   Switching Mixer   ├──► Dest 1 L/R
Control ──►│      (Group N)      ├──► Dest 2 L/R
           │                     ├──► Dest 3 L/R
           │                     ├──► Dest 4 L/R
           └─────────────────────┘

GUID

SwMx - NT_MULTICHAR('S', 'w', 'M', 'x')

Specifications

Spec	Range	Default	Description
Groups	1-4	1	Number of switch/mix groups

Parameters

Global (Page 0)

Parameter	Range	Default	Description
Bypass	Off/On	Off	Bypass all processing
Global Slew	0-5000 ms	10 ms	Default slew time

Per Group (Pages 1-4)

Parameter	Range	Default	Description
Input A L	Bus 0-28	Auto	Input A left/mono bus
Input A R	Bus 0-28	0 (mono)	Input A right bus (0=mono)
Input B L	Bus 0-28	Auto	Input B left/mono bus
Input B R	Bus 0-28	0 (mono)	Input B right bus (0=mono)
Control	Bus 0-28	Auto	Control CV input bus
Volume A	-40 to +6 dB	0 dB	Input A volume
Volume B	-40 to +6 dB	0 dB	Input B volume
Ctrl Type	Enum	Unipolar	Control response type
Curve	Enum	Equal Power	Crossfade curve
Crossfade	0-10	0	Per-group slew time
MIDI Enable	Off/On	Off	Enable MIDI control
MIDI Channel	1-16	1	MIDI channel
MIDI CC	0-127	Group #	MIDI CC number
Dest Count	1-4	1	Number of output destinations
Dest 1-4 L/R	Bus 0-28	Auto/0	Output destination buses

Control Types

Type	Input Range	Position 0	Position 1
Unipolar	0V to +10V	0V	+10V
Bipolar	-5V to +5V	-5V	+5V
Uni Rev	0V to +10V	+10V	0V
Bi Rev	-5V to +5V	+5V	-5V
Trigger	Rising edge	Toggle A	Toggle B
Trig Rev	Rising edge	Toggle B	Toggle A
Gate	Gate signal	Low = A	High = B
Gate Rev	Gate signal	Low = B	High = A

Crossfade Curves

Curve	Formula	Use Case
Linear	A = 1-x, B = x	Simple mixing
Equal Power	A = cos(x·π/2), B = sin(x·π/2)	Constant loudness
S-Curve	t = x²(3-2x), A = 1-t, B = t	Smooth DJ-style

Building

This plugin uses the official Disting NT API. To build:

1. Get the distingNT_API from Expert Sleepers
2. Install ARM cross-compilation toolchain
3. Build:

# Example with ARM GCC
arm-none-eabi-g++ -std=c++17 -O2 -mcpu=cortex-m7 \
    -I/path/to/distingNT_API/include \
    -c SwitchingMixer.cpp -o SwitchingMixer.o

arm-none-eabi-g++ -shared -o SwMx.ntplugin SwitchingMixer.o

4. Copy .ntplugin to Disting NT SD card plugins folder

Usage Examples

Simple A/B Crossfader

• Set Control Type to "Unipolar"
• Send 0-10V CV to control input
• 0V = Input A, 10V = Input B

Gate-Controlled Switch

• Set Control Type to "Gate"
• Send gate signal to control
• Low = Input A, High = Input B
• Use Slew for smooth transitions

MIDI-Controlled Crossfader

• Enable MIDI
• Set channel and CC
• CC 0 = Input A, CC 127 = Input B

Technical Notes

• Sample rate: 48kHz (assumes standard Disting NT rate)
• Zero latency (no lookahead)
• Output is additive to destination buses
• All signals ±10V compatible

Author

Me!

License

MIT License