test-input-level

name	test-input-level
description	Record a short sample from the active input device, compute peak/RMS levels, and recommend gain adjustments. Use to verify a mic preset is producing clean, well-leveled audio for voice dictation or recording.

test-input-level

Inputs

• duration_sec — recording length. Default 5.
• source_name — optional PipeWire/Pulse source name. If absent, records from the default source.

Steps

1. Pick a tool

Prefer parecord (pulseaudio/pipewire-pulse) since it's near-universal on modern Linux. Fall back to pw-record. Confirm one is installed:

command -v parecord >/dev/null || command -v pw-record >/dev/null \
  || { echo "Need parecord or pw-record. Install pulseaudio-utils or pipewire-cli."; exit 1; }
command -v sox >/dev/null \
  || { echo "Need sox for level analysis. Install with your package manager."; exit 1; }

2. Record

TMP=$(mktemp --suffix=.wav)
trap 'rm -f "$TMP"' EXIT

if [ -n "$source_name" ]; then
  parecord --device="$source_name" --file-format=wav "$TMP" &
else
  parecord --file-format=wav "$TMP" &
fi
REC_PID=$!
sleep "${duration_sec:-5}"
kill "$REC_PID" 2>/dev/null
wait "$REC_PID" 2>/dev/null || true

Tell the user when recording starts and stops — they need to be talking at a normal level during the window.

3. Analyze

sox "$TMP" -n stats 2>&1

sox stats reports peak (Pk lev dB), RMS (RMS lev dB), DC offset, crest factor, etc.

4. Recommend

Apply these heuristics:

• Peak above -3 dB → too hot. Reduce input gain or autogain target.
• Peak below -20 dB → too quiet. Raise gain.
• Sweet spot for voice dictation: peak between -12 and -6 dB, RMS around -20 to -16 dB.
• DC offset > 0.01 → check that DC removal / high-pass is on in the active preset.
• Crest factor > 20 dB → very dynamic; compression / autogain may help dictation accuracy.

Report the numbers and the recommendation. Offer to:

1. Re-run after the user adjusts gain in the OS mixer or preset
2. Run voice-dictation-setup if no clean preset is loaded yet