ADR 0007 Full Duplex AEC

ADR 0007 — Full-duplex barge-in and acoustic echo cancellation

Status: Accepted
Date: 2026-08-05
Milestone: Phase 2 (P2.5)

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Context

Phase 1 ships audio.duplex: half: wake and VAD are disabled while TTS plays so HDMI echo does not look like user speech. Full duplex needs AEC and a playback reference channel.

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Decision

1. Default remains half until hallway soak shows acceptable false-barge rates.
2. Reference = PipeWire/Pulse monitor of the speaker sink into software AEC.
3. When duplex: full, barge-in cancels speak and re-opens listen.

Full text: docs/adr/0007-full-duplex-aec.md in the main repo.

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Related

• ADR Index
• Speech