Channel Plan, DSP Outputs, And Amplifier Map
A channel plan is the authoritative record of every physical audio path. It must distinguish source channels, decoded or rendered channels, DSP paths, converter outputs, amplifier channels, passive branches, and physical drivers.
The Complete Row
| Source role | DSP input | Route / matrix | Processing | DSP output / DAC | Amplifier | Load / driver | Fault and mute |
|---|---|---|---|---|---|---|---|
| front left music | IN 1 | FL direct | HPF, EQ, delay, limiter | OUT 1 | A1 CH1 | left tweeter | mute group front-high |
| front left music | IN 1 | FL direct | BPF, EQ, delay, limiter | OUT 2 | A1 CH2 | left midrange | mute group front-mid |
| derived or native center | renderer / matrix | document coefficients | bandwidth, delay, EQ, limiter | OUT 5 | A2 CH1 | center wideband | preserve alerts |
| sub bus | sub matrix | document sum and headroom | HPF, LPF, EQ, delay, limiter | OUT 9 | mono amp | verified load | remote and protection state |
Channel Count Is Not One Number
- Source channels: what enters the system before decode, downmix, upmix, or matrixing.
- Rendered channels: outputs produced by a decoder or renderer for a selected layout.
- DSP processing paths: independent filter, delay, level, routing, and protection paths.
- Analog outputs: actual DAC and line-stage channels available from the hardware.
- Amplifier channels: independently powered outputs, including bridge and shared-supply constraints.
- Physical drivers: individual active drivers or passive branches connected to one amplifier channel.
Active, Passive, And Hybrid Mapping
| Architecture | DSP and amplifier use | What remains shared | Verification |
|---|---|---|---|
| fully active | one processing and amplifier path per driver | source and electrical resources | each driver and every combination |
| passive component set | one amplifier path feeds the passive network | level, phase, load, heat, and protection within the branch | network input, driver terminals, and acoustic sum |
| hybrid | some active bands and some passive branches | mixed control and protection limits | document every branch explicitly |
Before Power-Up
- Verify every source, DSP, DAC, amplifier, and driver label against the map.
- Confirm polarity and bridge or floating-output topology.
- Load a protected commissioning preset with conservative filters and levels.
- Play a unique low-level identification signal through one route at a time.
- Verify mute, remote, fault, turn-on, turn-off, and recovery sequences.
- Measure the clean input and output limit of every critical boundary.
Never infer audio transport from control wiring.
I²C, SPI, USB programming, or a shared microcontroller can configure multiple DSPs without carrying the audio between them. Document serial audio clocks, data lanes, analog links, or network audio separately.