{
  "title": "Countdown",
  "author": "ckvoiceover",
  "source_url": "https://freesound.org/people/ckvoiceover/sounds/401342/",
  "download_url": "https://cdn.freesound.org/previews/401/401342_6652552-hq.mp3",
  "source_sha256": "a64d657633593802c3c7b70463bd5cb6317646c5a462ca7b5dae28569c5ed8c4",
  "license": "CC BY 4.0",
  "license_url": "https://creativecommons.org/licenses/by/4.0/",
  "accessed": "2026-10-14",
  "human_provenance": "Original creator describes a male 10-to-1 spoken countdown; source taxonomy is Solo speech, with human/male/spoken tags. Not a TTS asset.",
  "source_duration_seconds": 10.84953125,
  "processing": "Extract final three words; mono32k PCM16; DC removal; RMS target.12 capped at peak.82;6ms boundary fades. No pitch shifting, voice cloning or speech synthesis.",
  "segmentation": "Source has10 speech regions separated by silence; the final3 regions correspond to3/2/1 in the creator-described descending10-to-1 sequence. See audio-asr-validation.json for independent speech recognition.",
  "clips": [
    {
      "number": 3,
      "text": "three",
      "source_interval_seconds": [
        7.98,
        8.6
      ],
      "duration_seconds": 0.62,
      "gain": 1.22852623462677,
      "peak": 0.7641096711158752,
      "rms": 0.11999989300966263,
      "path": "assets/audio/countdown-3.wav",
      "bytes": 39724,
      "sha256": "c6ea1d5009fcb338772b15bbe2a655627ca5fd30b939a92208f76e10c3491db9"
    },
    {
      "number": 2,
      "text": "two",
      "source_interval_seconds": [
        9.17,
        9.72
      ],
      "duration_seconds": 0.55,
      "gain": 0.8445001244544983,
      "peak": 0.8199999928474426,
      "rms": 0.1069895327091217,
      "path": "assets/audio/countdown-2.wav",
      "bytes": 35244,
      "sha256": "c3d5ae44b832fafcd90ae92e32c5685ea973f2947b4154d7be812b1316151ac0"
    },
    {
      "number": 1,
      "text": "one",
      "source_interval_seconds": [
        10.24,
        10.84953125
      ],
      "duration_seconds": 0.60953125,
      "gain": 1.4935346841812134,
      "peak": 0.7228387594223022,
      "rms": 0.11999986320734024,
      "path": "assets/audio/countdown-1.wav",
      "bytes": 39054,
      "sha256": "39233529c5a25d350af446523d0a0ccf5bcd677fdf9ae1727a3fcaf919ef07c2"
    }
  ],
  "credit": "Countdown by ckvoiceover / Freesound — CC BY4.0. Adapted: excerpted three/two/one, normalized and trimmed.",
  "verification": "Decoded and segmented from waveform; automated ASR separately recorded. No direct listening or browser playback claimed."
}