Checks phase coherence: overall and per-band correlation, and polarity detection.
Parameters
| Parameter | Type | Default | Description |
|---|---|---|---|
| file_path | string | required | Path to stereo audio file |
Example Output
Illustrative summary; MCP responses use structured JSON.
$ analyze_phase stereo-bus.wav
Phase Analysis Overall coherence: 0.84 Polarity: OK (positive correlation)
Per-band Coherence: Sub (20-80 Hz): 0.98 Low (80-250 Hz): 0.92 Low-mid (250-500 Hz): 0.89 Mid (500-2k Hz): 0.83 High (2k-8k Hz): 0.68 Air (8k-20k Hz): 0.55
What the Numbers Mean
-
Overall Coherence – Pearson correlation between the left and right waveforms. Values range from -1 to 1. Positive correlation means shared signal; negative correlation indicates cancellation risk when summed. It is measured separately from the per-band values.
-
Polarity – The polarity flag is set when overall correlation falls below the configured threshold (-0.5 by default). It is a diagnostic clue, not proof of a wiring fault.
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Per-band Coherence – Phase coherence broken down by frequency range. Low frequencies should be highly coherent (0.9+) for solid bass in mono. Higher frequencies can be lower (0.5-0.8) – that’s normal stereo width from reverb, panning, and stereo effects.
analyze_phase doesn’t measure time delay between channels. To estimate delay between two files (e.g. two mics on the same source), use compare_phase.
Example Prompts
Mono compatibility
Check if my mix is mono-compatible – analyze the phase of mix-stereo.wav
Phase issues
Are there phase cancellation problems in my drum overheads?
Bass check
Is the low end in phase? I want it to translate to mono club systems
Related Tools
- analyze_stereo – Width and balance measurement (complementary to phase analysis)
- compare_phase – Compare phase between two different sources
- detect_problems – Checks clipping, hum, DC offset, and spectral problems
Pro tip
Low or negative bass correlation deserves a mono audition. Check timing, polarity, and stereo processing before deciding whether to narrow the low end.