Sound Array
Concept
Audio processing system using Raspberry Pi and microphone arrays for spatial sound analysis. Captures multi-channel audio from USB/HAT arrays (ReSpeaker, Matrix), computes Time of Arrival (ToA) for sound localization, and applies beamforming for directional isolation. Classifies sources — vehicles (engine sounds), aircraft, wildlife (birds) — and streams processed audio or metadata to a remote desktop for analysis.
Runs on Raspberry Pi 4+ at standard sampling rates (44.1–48 kHz), targeting human-audible range.
Quick Facts
| Status | Active |
What This Is
An exploration-focused audio processing system using Raspberry Pi and microphone arrays. It focuses on spatial audio (ToA, beamforming) and classification (vehicles, wildlife) using an “analyst” agent approach.
Core Value
The ability to capture, localize, and classify complex soundscapes on edge devices or via remote streaming, providing structured insights to an agent framework.
Stakeholders
- Primary: Developer (exploration & play)
- Secondary: Agent Framework (consumer of audio analysis)
Context
# Background
- Inspired by the potential of spatial audio on low-cost hardware.
- Focus on “analysts” rather than real-time reactive agents initially.
- Interested in vehicle engine sounds (cars, aircraft, helicopters) and wildlife (birds, bats - audible range).
# Stated Constraints
- Hardware: Raspberry Pi (v4+).
- Audio Range: Human audible range (sampling rates ~44.1-48kHz).
- Platform: Edge (Pi) or remote streaming to desktop.
Requirements
# Validated
(None yet — ship to validate)
# Active
- Multi-channel audio capture from USB/HAT microphone arrays.
- Time of Arrival (ToA) estimation for sound localization.
- Beamforming for directional sound isolation and noise reduction.
- Sound classification for vehicles (engine sounds) and wildlife.
- Streaming interface to send raw or processed audio to a remote desktop.
- Integration interface for “analyst” agents to query sound metadata.
# Out of Scope
- Ultrasonic capture (>20kHz) — focusing on human-audible range for now.
- Custom hardware design — using off-the-shelf arrays (ReSpeaker/Matrix).
- Real-time “active defense” or reactive triggers — focus on analysis first.
Key Decisions
| Decision | Rationale | Outcome |
|---|---|---|
| “Analyst” Focus | Allows for deeper data exploration over reactive triggers. | — Pending |
| Audible Range Only | Bats/birds to be tracked within human-audible spectrum to simplify hardware. | — Pending |
| Agnostic/USB Priority | USB arrays offer easier initial setup and portability. | — Pending |
Last updated: 2026-02-13 after initialization