KCC SoundLab

Home Assistant based car-audio DSP tuning, measurement and calibration toolkit.

KCC SoundLab is being built around the current KCC car-audio setup with Goldhorn P2 DSP Pro as the first supported DSP. The long-term goal is a guided tuning environment for channel setup, crossover, time alignment, measurement, EQ, presets and eventually controlled DSP write-back.

v0.6 is a tuning, crossover, measurement and EQ assistant. It stores tuning data inside the integration, but it does not yet write settings directly to the Goldhorn DSP.

v0.6 features

• Configure a Goldhorn P2 DSP Pro workspace from the Home Assistant UI.
• Model 1–12 active outputs while keeping Home Assistant clean with only two status entities.
• Edit channel name, speaker, role and physical location directly in SoundLab.
• Store gain, phase, polarity, HPF and LPF settings in the internal workspace.
• Automatically calculate physical time-alignment delay from the furthest speaker.
• Add HolmImpulse fine correction per channel and track polarity/alignment verification.
• Save up to 20 complete tuning snapshots.
• Measurement Center with up to 20 persistent HolmImpulse measurement sessions.
• Crossover Lab for two-output electrical handoff setup and comparison.
• EQ / Target Curve workspace with 31 EQ bands per output.
• Each EQ band stores enabled state, frequency, gain and Q.
• Electrical EQ preview on a logarithmic frequency graph.
• Global target curve overlay with Flat, KCC SQ Draft, Warm and Custom modes.
• Six editable target-curve gain anchors from 20 Hz to 20 kHz.
• Copy all EQ bands from one output to another.
• Reset one output back to a flat 31-band EQ.
• EQ and target curve are included in tuning snapshots.
• Compact status entity exposes active EQ-band count and current target curve without adding new parameter entities.
• Open SoundLab directly from the Home Assistant sidebar.

Workspaces

• Overview – system summary, channel map, presets and final delay overview.
• Channels – channel setup, gain/phase/polarity and per-channel filter controls.
• Time Alignment – physical distance, HolmImpulse fine correction, verification and final delay.
• Crossover – paired-output filter comparison, handoff analysis and direct HPF/LPF editing.
• EQ – 31-band channel EQ, electrical preview, copy/reset tools and target curve.
• Measurement – HolmImpulse sessions, channel-by-channel results and arrival comparison.
• Presets – save, restore and delete complete tuning snapshots including EQ/target data.

Installation for prototype testing

HACS custom repository

1. In HACS, open the menu and choose Custom repositories.
2. Add https://github.com/MVtag/KCC-SoundLab as an Integration repository.
3. Download KCC SoundLab.
4. Restart Home Assistant.
5. Go to Settings → Devices & services → Add integration and search for KCC SoundLab.
6. Select Goldhorn P2 DSP Pro, enter the vehicle name and choose the number of active outputs.
7. Open KCC SoundLab from the Home Assistant sidebar.

Updating from earlier versions

The internal workspace remains backward compatible with existing channel/tuning and measurement data. When upgrading to v0.6, each existing output receives a flat default 31-band EQ and the target curve defaults to Flat. Existing gain, crossover, phase, time-alignment, measurement and snapshot data remain intact.

No new Home Assistant parameter entities are created.

Current KCC five-channel profile

Output	Speaker	Role	Default location
OUT A	BLAM FRS2N50 L	Full-range	Front left dash
OUT B	BLAM FRS2N50 R	Full-range	Front right dash
OUT C	BLAM 165 LSQ L	Midbass	Front left door
OUT D	BLAM 165 LSQ R	Midbass	Front right door
OUT E	BLAM SuperSub12	Subwoofer	Boot / trunk

All channel names, speakers, roles and locations are editable from the Channels workspace. The backend supports up to 12 active outputs.

Time alignment

physical_delay_ms = (furthest_distance_cm - speaker_distance_cm) / 34.3

recommended_delay_ms = physical_delay_ms + fine_delay_ms

The recommended delay is clamped to 0–20 ms. Positive fine correction adds delay; negative correction removes delay down to 0 ms.

Crossover Lab

Select any two active outputs. SoundLab orders them as a low-frequency and high-frequency side based on their roles and compares:

low-side LPF ↔ high-side HPF

The handoff is classified as Matched, Gap or Overlap using the electrical crossover frequencies. SoundLab also shows octave offset plus whether filter type and slope match.

The plotted curves are setup sketches based on filter frequency and nominal dB/oct slope. They are not acoustic predictions. Final crossover decisions must be verified from the measured summed response and phase after installation.

EQ / Target Curve

The P2 DSP Pro workspace uses 31 EQ bands per output. SoundLab stores the following values for each band:

• enabled / disabled,
• frequency from 20 Hz to 20 kHz,
• gain from -12 dB to +12 dB,
• Q from 0.1 to 20.

The EQ graph is an electrical preview used for workspace planning. It is not a substitute for an acoustic measurement.

The target curve is a separate reference overlay. The built-in KCC SQ Draft and Warm curves are starting references only; they do not automatically apply EQ. Editing any target point changes the target mode to Custom.

A complete tuning snapshot stores the channel EQ and the active target curve alongside crossover, gain, phase and time alignment.

Measurement Center

Create one session per microphone/listening position and keep the same HolmImpulse timing/reference arrangement across all channels in that session. SoundLab can then compare impulse arrival times consistently.

relative_delay_ms = latest_impulse_ms - channel_impulse_ms

This is measurement evidence, not automatic DSP write-back. Final tuning changes remain deliberate and are entered through the relevant SoundLab workspace.

Frontend architecture

The SoundLab UI is bundled with the integration and registered as a Home Assistant custom sidebar panel. The panel reads and writes the persistent tuning/measurement workspace through a small KCC SoundLab WebSocket API instead of creating a Home Assistant entity for every DSP parameter.

Frontend module imports are versioned with the integration version. CI validates JavaScript syntax and verifies that local module cache keys exactly match manifest.json to prevent stale mixed-version frontend modules.

Planned next steps

• Subwoofer phase/alignment workflow with guided comparisons.
• Measurement-aware EQ suggestions after real measurement data is available.
• Import/compare measurement files and tuning sessions.
• Configurable car/channel-map positions beyond the first five-channel profile.
• Research direct Goldhorn controller/protocol support and write-back.