Dynamics Analyzer — Crest Factor and Dynamic Range

Profiles the dynamic characteristics of an audio file — how much variation exists between quiet and loud moments, and how transient or compressed the material is.

Parameters

Parameter Type Default Description
file_path string required Path to audio file
channel string "all" Channel to analyze: "left", "right", or "all"
frame_length number 2048 Analysis frame size in samples

Example Output

$ analyze_dynamics drums.wav

Dynamics Analysis RMS level: -12.4 dB Peak level: -0.3 dB Crest factor: 12.1 dB Dynamic range: 14.8 dB Complexity: 0.72

What the Numbers Mean

  • RMS Level — The average power level. Represents perceived loudness better than peak. Professional mixes typically sit between -18 dB and -10 dB RMS depending on genre.

  • Peak Level — The highest sample value. Compare to RMS to understand how transient the material is. Drums have high peaks relative to RMS; compressed vocals have low peaks relative to RMS.

  • Crest Factor — Peak minus RMS in dB. Higher crest factor = more transient/punchy. Drums: 12-20 dB. Compressed vocals: 4-8 dB. Over-limited masters: 2-4 dB.

  • Dynamic Range — The difference between the loudest and quietest meaningful passages. Unlike LRA (loudness range), this is a pure amplitude measurement.

  • Complexity — A 0-1 score indicating how much the dynamics change over time. Higher = more varied dynamics (live performance, classical). Lower = more consistent (electronic, heavily compressed).

Example Prompts

Compression check

How compressed are my vocals? Analyze dynamics of vocals.wav

Transient health

Check if my drums still have good transients after processing

Before/after comparison

Compare the dynamics of drums-raw.wav vs drums-processed.wav — did I kill the punch?

  • analyze_loudness — LUFS-based loudness (broadcast standard) vs dB-based dynamics here
  • detect_problems — Can identify over-compression via clipping detection
  • full_diagnostic — Includes dynamics analysis in comprehensive measurement

Pro tip

A crest factor below 6 dB on drums usually means over-compression. You’ve squashed the transients that make drums sound alive. Consider parallel compression instead — blend compressed and uncompressed signals.