acoustic-room-mode-radar

Acoustic Room Mode Radar (acoustic-room-mode-radar) is a deterministic Model Context Protocol (MCP) server engineered for room acoustics, home studio design, podcast vocal booths, and audio monitoring environments. It provides zero-hallucination mathematical engines for standing wave room modes (Axial, Tangential, Oblique), Bonello and Bolt dimensional criteria compliance, Schroeder crossover cutoff frequency, Sabine & Norris-Eyring RT60 reverberation decay, and optimal speaker/sweet-spot placement.

🎮 Live Interactive Web Simulator: Experience the zero-install 2D blueprint simulator, sweet-spot 38% rule calculator, and real-time room mode spectrum directly in your browser:
👉 https://tudadada.github.io/acoustic-room-mode-radar/

Capabilities & Tools Included

1. calculate_room_modes

Calculates discrete acoustic standing wave room modes up to a cutoff frequency for rectangular enclosures.

• Rayleigh Wave Model: Computes exact frequencies ($f_{p,q,r} = \frac{c}{2}\sqrt{(p/L)^2 + (q/W)^2 + (r/H)^2}$) for all Axial (0 dB), Tangential (-3 dB), and Oblique (-6 dB) modes.

• Resonance Clustering Detection: Identifies severe degeneracies and modal stacking closer than 1.5 Hz apart.

• Bass Isolation Holes: Detects wide gaps (> 18 Hz) below 120 Hz causing hollow bass response.

• Bonello 1/3-Octave Criterion (1981): Audits monotonic mode count growth per third-octave band to spot acoustic dips and colorations.

• Bolt Area Compliance: Checks room dimensional ratios ($W/H$ and $L/H$) against Richard Bolt's envelope of favorable acoustic proportions.

2. calculate_schroeder_frequency

Computes the Schroeder cutoff frequency ($f_s \approx 2000 \sqrt{RT_{60}/V}$), establishing the four operational acoustic regimes:

• Zone A (Pressurization): $0 \text{ Hz} \to f_{min}$ (Room acts as sealed pressure chamber).

• Zone B (Discrete Modes): $f_{min} \to f_s$ (Standing waves and bass resonance dominate).

• Zone C (Diffusion Transition): $f_s \to 4f_s$ (Diffusers and broadband absorption take effect).

• Zone D (Specular Ray Acoustics): $> 4f_s$ (Ray acoustics, early reflections, mirror trick).

3. calculate_rt60_reverb_time

Calculates reverberation decay time (RT60) across 6 standard octave bands (125 Hz to 4000 Hz) using both Sabine and Norris-Eyring formulations.

• Substrate Database: Built-in absorption coefficients for drywall, concrete, glass, hardwood, ceramic tile, commercial carpet, heavy pile, acoustic foam (50mm), rigid fiberglass (100mm), and heavy velour curtains.

• Target Usage Presets: Compares current decay against professional targets (podcast_voiceover [0.22 - 0.32s], music_mixing_control [0.28 - 0.38s], home_theater [0.35 - 0.48s], audiophile_listening [0.45 - 0.60s]).

• Treatment Prescription: Calculates exact square meters of high-density acoustic treatment panels required to achieve the target decay.

4. calculate_speaker_listening_position

Calculates optimal listening sweet spot and stereo monitor coordinates.

• 38% Room Rule (Westhler Model): Pinpoints listening position at 38.2% (or fallback 44%) room length to balance first-mode nulls and second-mode peaks.

• Equilateral Triangle Geometry: Coordinates monitor spacing and toe-in aiming angles (30° inward).

• Speaker Boundary Interference Response (SBIR): Calculates first quarter-wavelength cancellation notches from rear and side walls, providing actionable placement adjustments.

Related MCP server: audio-calibration-mcp

Quick Start

Running directly via npx

npx -y acoustic-room-mode-radar

Claude Desktop Integration

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "acoustic-room-mode-radar": {
      "command": "npx",
      "args": ["-y", "acoustic-room-mode-radar"]
    }
  }
}

Cursor Integration

In Cursor Settings > Features > MCP Servers:

• Type: command

• Command: npx -y acoustic-room-mode-radar

Specification Authority & Verification

All calculations strictly adhere to:

• ISO 3382-1: Measurement of room acoustic parameters.

• Lord Rayleigh Theory of Sound: Rectangular acoustic cavity modal eigenvalues.

• Wallace Clement Sabine & Norris-Eyring: Diffuse field reverberation decay equations.

• Richard Bolt & Oscar Bonello Criteria: Statistical distribution of normal modes in small rooms.

License

MIT © datutu ceo@dottheworld.com