{
  "batch": "Audio Letters 06–10",
  "date": "2026-11-10",
  "source_zip": "Dr-Peter-Beter-HQ 01(1).zip",
  "source_zip_sha256": "4a9e301d5811d2ce8d0d54389de31da0221a533e53f9f2af7aa69d2c7cf66691",
  "profile": {
    "version": "PDB_AL_restoration_v2_2026-11-10",
    "cleanup_filter": "highpass=f=60:p=2,afftdn=nr=4:nf=-50:tn=1:ad=0.85:gs=10",
    "target_lufs_mono": -19.0,
    "preencode_true_peak_ceiling_dbtp": -2.5,
    "maximum_positive_gain_db": 6.0,
    "output_bitrate": "128k",
    "output_sample_rate": 44100,
    "output_channels": 1,
    "intermediate_codec": "pcm_f32le",
    "dynamic_compression": false,
    "silence_trimming": false,
    "ai_speech_reconstruction": false,
    "perceptual_listening_review": "User A/B preview pending; technical QC is not a listening review."
  },
  "summary": {
    "recordings": 10,
    "letters": 5,
    "decoded_duration_seconds": 16883.931428571428,
    "decoded_duration_hms": "04:41:24",
    "all_technical_qc_passed": true,
    "exact_sample_counts_preserved": true,
    "actual_source_and_output_hashes_verified": true,
    "embedded_artwork_bytes_preserved": true,
    "output_lufs_mono_min": -19.5,
    "output_lufs_mono_max": -19.4,
    "output_true_peak_dbtp_min": -6.5,
    "output_true_peak_dbtp_max": -3.0
  },
  "reproduction_script_sha256": "ca90aa1dbcbbd5d7ee59316aae6df5c05bf4a6cb8a694b7266583dde37cbb51e",
  "limitations": [
    "Technical validation is not subjective listening.",
    "Some hiss and hum remain; no recovery of lost source details is claimed.",
    "The noise-reduction setting is not a measurement of uniform improvement.",
    "Exact duration is measured from decoded samples, not estimated MP3 headers."
  ],
  "files": [
    {
      "id": "AL-06-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 06 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-06-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-06-Part-01.mp3",
      "output_filename": "PDB_AL-06-P01_Restored_v2.mp3",
      "source_sha256": "762fbbfa87cc609d5a05db3bb99f09bb5d2a6ac267828eea4599da72c2dac970",
      "source_bytes": 16937541,
      "output_sha256": "31774b50c6d75a5b5defc7e77f1b26f545d0870da5a6b9764177f5b7b3ab47ac",
      "output_bytes": 25240141,
      "source_metrics": {
        "integrated_lufs_mono": -19.7,
        "lra_lu": 2.8,
        "true_peak_dbtp": -6.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -6.035555,
        "rms_dbfs": -20.273682,
        "samples": 69546240,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.0122448979591
      },
      "clean_metrics": {
        "integrated_lufs_mono": -19.7,
        "lra_lu": 2.8,
        "true_peak_dbtp": -4.4,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.429444,
        "rms_dbfs": -20.293204,
        "samples": 69546240,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.0122448979591
      },
      "gain_db": 0.7,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 2.8,
        "true_peak_dbtp": -4.2,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -4.18057,
        "rms_dbfs": -20.03865,
        "samples": 69546240,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.0122448979591
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "5df60e161261a3cd496ea6112564410631db887289fd007d3306d3557c670afa"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "album": "Audio Letter No. 06"
        }
      }
    },
    {
      "id": "AL-06-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 06 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-06-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-06-Part-02.mp3",
      "output_filename": "PDB_AL-06-P02_Restored_v2.mp3",
      "source_sha256": "868ce29cc0844eb42f5b0ba12420540186b11396d1cda5ee04717e02e14e65cc",
      "source_bytes": 16261334,
      "output_sha256": "35c676b3ad5a120a7ae8cdf1e39ce1460c485b2e8c2550d8e816fe48e8eab8af",
      "output_bytes": 25241446,
      "source_metrics": {
        "integrated_lufs_mono": -21.0,
        "lra_lu": 2.6,
        "true_peak_dbtp": -5.8,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.911224,
        "rms_dbfs": -21.715209,
        "samples": 69549696,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.090612244898
      },
      "clean_metrics": {
        "integrated_lufs_mono": -21.0,
        "lra_lu": 2.7,
        "true_peak_dbtp": -4.4,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.52111,
        "rms_dbfs": -21.733936,
        "samples": 69549696,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.090612244898
      },
      "gain_db": 1.9,
      "gain_limited_by_peak": true,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.7,
        "true_peak_dbtp": -3.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -3.038129,
        "rms_dbfs": -20.279478,
        "samples": 69549696,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1577.090612244898
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "1fb2f07d6ea191d708f5d8e1dd9d3502295534a3d41a273b2cc4b28fb1d1bd0a"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 06",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-07-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 07 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-07-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-07-Part-01.mp3",
      "output_filename": "PDB_AL-07-P01_Restored_v2.mp3",
      "source_sha256": "e75f87581e928bfac3f83c3d965ecbee6381f8891881874d78804461bc667fc7",
      "source_bytes": 18558976,
      "output_sha256": "45efc62de373a07d3e83efdde3f69c3fd9950e8800b00c2a254ab5551b808183",
      "output_bytes": 27308254,
      "source_metrics": {
        "integrated_lufs_mono": -16.2,
        "lra_lu": 4.0,
        "true_peak_dbtp": -5.9,
        "dc_offset": -7e-06,
        "sample_peak_dbfs": -5.914783,
        "rms_dbfs": -16.100771,
        "samples": 75246336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.2661224489796
      },
      "clean_metrics": {
        "integrated_lufs_mono": -16.2,
        "lra_lu": 4.0,
        "true_peak_dbtp": -3.0,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -3.023462,
        "rms_dbfs": -16.153508,
        "samples": 75246336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.2661224489796
      },
      "gain_db": -2.8,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 4.0,
        "true_peak_dbtp": -6.3,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -6.267958,
        "rms_dbfs": -19.398991,
        "samples": 75246336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.2661224489796
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "3c855b9cffd2165beb1b6be6502ef49b49e83cddae4e3a97e6882657f9ada90d"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 07",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-07-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 07 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-07-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-07-Part-02.mp3",
      "output_filename": "PDB_AL-07-P02_Restored_v2.mp3",
      "source_sha256": "1032855eceb2b465c3636f322a6e9e8c8f513fca74601f11fe4951f90ecede54",
      "source_bytes": 18731266,
      "output_sha256": "fc4011b7f2efbd8f5785e047c7a431324659f82e673ad78407ab396da19bc660",
      "output_bytes": 27307001,
      "source_metrics": {
        "integrated_lufs_mono": -15.3,
        "lra_lu": 3.6,
        "true_peak_dbtp": -5.9,
        "dc_offset": 1.5e-05,
        "sample_peak_dbfs": -5.942908,
        "rms_dbfs": -15.068355,
        "samples": 75242880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.187755102041
      },
      "clean_metrics": {
        "integrated_lufs_mono": -15.3,
        "lra_lu": 3.6,
        "true_peak_dbtp": -2.4,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -2.380222,
        "rms_dbfs": -15.123965,
        "samples": 75242880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.187755102041
      },
      "gain_db": -3.7,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 3.6,
        "true_peak_dbtp": -6.5,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -6.519812,
        "rms_dbfs": -19.269396,
        "samples": 75242880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1706.187755102041
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "6f5057d70eaf29c5df8bc9b6fa304eda5bce0762f645c9b57ba9ebcdf12b870b"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 07",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-08-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 08 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-08-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-08-Part-01.mp3",
      "output_filename": "PDB_AL-08-P01_Restored_v2.mp3",
      "source_sha256": "13d8a35f41f483d9ec8881003d4e1fd08ee9f529ac0ca3c408508b256213e779",
      "source_bytes": 17983979,
      "output_sha256": "042daab31432d9a6c24aced054966f380fddfd9ccb0f7f46f89f1964a753a3c2",
      "output_bytes": 27267661,
      "source_metrics": {
        "integrated_lufs_mono": -18.2,
        "lra_lu": 3.8,
        "true_peak_dbtp": -6.1,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -6.100624,
        "rms_dbfs": -18.231813,
        "samples": 75134592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1703.7322448979592
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.2,
        "lra_lu": 3.8,
        "true_peak_dbtp": -4.4,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.396447,
        "rms_dbfs": -18.255855,
        "samples": 75134592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1703.7322448979592
      },
      "gain_db": -0.8,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 3.8,
        "true_peak_dbtp": -5.6,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.638886,
        "rms_dbfs": -19.50144,
        "samples": 75134592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1703.7322448979592
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "0a4c044aba086fc5447ff99c7f557d867632a39cb6d413bcc6d82256179ea30c"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "album": "Audio Letter No. 08"
        }
      }
    },
    {
      "id": "AL-08-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 08 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-08-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-08-Part-02.mp3",
      "output_filename": "PDB_AL-08-P02_Restored_v2.mp3",
      "source_sha256": "e5f5973002125f953480520b57779112a8f6c83c90516fcd77c5688603093c32",
      "source_bytes": 17918781,
      "output_sha256": "4341d24f3f3f3d67b5c0481c23556020e01805e9d1ae83d92634d31773d8fdf2",
      "output_bytes": 27479567,
      "source_metrics": {
        "integrated_lufs_mono": -20.3,
        "lra_lu": 3.5,
        "true_peak_dbtp": -6.1,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -6.099571,
        "rms_dbfs": -20.046295,
        "samples": 75718656,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1716.9763265306121
      },
      "clean_metrics": {
        "integrated_lufs_mono": -20.3,
        "lra_lu": 3.5,
        "true_peak_dbtp": -5.1,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.069376,
        "rms_dbfs": -20.067171,
        "samples": 75718656,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1716.9763265306121
      },
      "gain_db": 1.3,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 3.5,
        "true_peak_dbtp": -4.2,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.211102,
        "rms_dbfs": -19.212864,
        "samples": 75718656,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1716.9763265306121
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "d103bbc636ca979899b89588480447f3efa42860ed02a5231388a0a49d8b458e"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "album": "Audio Letter No. 08"
        }
      }
    },
    {
      "id": "AL-09-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 09 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-09-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-09-Part-01.mp3",
      "output_filename": "PDB_AL-09-P01_Restored_v2.mp3",
      "source_sha256": "1daabe27bc4d2c010bd09e85bbff3715db5d5dc5da92d245669dc853286e8939",
      "source_bytes": 18475541,
      "output_sha256": "5a8e3376880e4a883580bdb0600f9340fba8d67855cd3c6cee8ac10fe89829e9",
      "output_bytes": 28150904,
      "source_metrics": {
        "integrated_lufs_mono": -21.3,
        "lra_lu": 2.9,
        "true_peak_dbtp": -6.1,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -6.098954,
        "rms_dbfs": -21.404729,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "clean_metrics": {
        "integrated_lufs_mono": -21.3,
        "lra_lu": 2.9,
        "true_peak_dbtp": -4.7,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.7224,
        "rms_dbfs": -21.424081,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "gain_db": 2.2,
      "gain_limited_by_peak": true,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.9,
        "true_peak_dbtp": -3.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -2.95965,
        "rms_dbfs": -19.669621,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "cc344bbb7125c71b711c56338437185712b78d45c92fbd6a7c284114087befb5"
          },
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "355ede165efc282816e454df700f1ceae04636a5828d93cb479b827de7e2bb43"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 09",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-09-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 09 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-09-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-09-Part-02.mp3",
      "output_filename": "PDB_AL-09-P02_Restored_v2.mp3",
      "source_sha256": "c5672c928559ce1162066cc9714984f7b9d3028560362ed43e687331d8d8d11f",
      "source_bytes": 18321943,
      "output_sha256": "bf9ea137e59b54c0c6486cceafae18d97740092db4c5ccce72fcb5fb330f5635",
      "output_bytes": 28150904,
      "source_metrics": {
        "integrated_lufs_mono": -20.3,
        "lra_lu": 3.1,
        "true_peak_dbtp": -6.0,
        "dc_offset": -1e-06,
        "sample_peak_dbfs": -5.981139,
        "rms_dbfs": -20.430423,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "clean_metrics": {
        "integrated_lufs_mono": -20.3,
        "lra_lu": 3.1,
        "true_peak_dbtp": -4.1,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -4.125728,
        "rms_dbfs": -20.45951,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "gain_db": 1.3,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 3.1,
        "true_peak_dbtp": -3.3,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -3.353207,
        "rms_dbfs": -19.604964,
        "samples": 77550336,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1758.5110204081632
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "e0baa33f01b4649ce71a99293d57b3702f90fa1878a8b99347329d580624b1fc"
          },
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "1cf3d62fe7cc4ba9945a15f74f8b9b5e742b011d4055018ad4d5f1da8870e0d0"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 09",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-10-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 10 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-10-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-10-Part-01.mp3",
      "output_filename": "PDB_AL-10-P01_Restored_v2.mp3",
      "source_sha256": "9905f36b377121b11da8d35a2362e5529aa581f019cd30cfa2919ce3ee70f0b7",
      "source_bytes": 17960976,
      "output_sha256": "b65161912dfba193f6ca00dbaa4e6db8bdf73d6c60cd3a486b63d569e33bc300",
      "output_bytes": 27057984,
      "source_metrics": {
        "integrated_lufs_mono": -20.5,
        "lra_lu": 3.2,
        "true_peak_dbtp": -6.0,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -6.062114,
        "rms_dbfs": -20.683427,
        "samples": 74519424,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.7828571428572
      },
      "clean_metrics": {
        "integrated_lufs_mono": -20.5,
        "lra_lu": 3.3,
        "true_peak_dbtp": -4.4,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.420127,
        "rms_dbfs": -20.710911,
        "samples": 74519424,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.7828571428572
      },
      "gain_db": 1.5,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 3.2,
        "true_peak_dbtp": -3.4,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -3.361722,
        "rms_dbfs": -19.656462,
        "samples": 74519424,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.7828571428572
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "f8c6af2ed567d6883f9d28c75e5889d1b4e50978b8b91a13d695312a6afacdb0"
          },
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "06012e246ff95ca3a428f55d7af4e3334eac199d19ace66447b18bb5762dd440"
          },
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "298ea519ac885fc4fcf51c2f84d1dba8e849fdb3543585322e68f2f15708d134"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 10",
          "date": "2006"
        }
      }
    },
    {
      "id": "AL-10-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 10 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-10-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-10-Part-02.mp3",
      "output_filename": "PDB_AL-10-P02_Restored_v2.mp3",
      "source_sha256": "af8a7653c8aba80a51cc1555cb23cd25186c86adda4031906ab5c084fbe60024",
      "source_bytes": 16417424,
      "output_sha256": "01e2ac2dd1d2d36d2ec582007d6b9d391d42edf3e31f3e58863f439b57830244",
      "output_bytes": 27045760,
      "source_metrics": {
        "integrated_lufs_mono": -20.8,
        "lra_lu": 2.9,
        "true_peak_dbtp": -6.0,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -6.030607,
        "rms_dbfs": -21.387117,
        "samples": 74522880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.8612244897959
      },
      "clean_metrics": {
        "integrated_lufs_mono": -20.8,
        "lra_lu": 2.9,
        "true_peak_dbtp": -4.2,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.231677,
        "rms_dbfs": -21.417221,
        "samples": 74522880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.8612244897959
      },
      "gain_db": 1.7,
      "gain_limited_by_peak": true,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.9,
        "true_peak_dbtp": -3.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -2.988115,
        "rms_dbfs": -20.162748,
        "samples": 74522880,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1689.8612244897959
      },
      "checks": {
        "exact_decoded_sample_count": true,
        "finite_samples": true,
        "true_peak_at_most_minus_1_5_dbtp": true,
        "mono_44100": true,
        "mp3_128k": true,
        "original_hash_unchanged": true,
        "no_output_decoder_warnings": true
      },
      "technical_qc_passed": true,
      "package_audit": {
        "actual_source_hash_verified": true,
        "actual_output_hash_verified": true,
        "embedded_artwork_identical": true,
        "artwork_images": [
          {
            "mime": "image/png",
            "picture_type": 0,
            "description": "",
            "image_bytes": 6708,
            "image_sha256": "0fb6904b7eaf12ae0bf59287609b8ac28e5d996a79ff5c84ef5aba8ac61ee942"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dan Holt",
          "album": "Audio Letter No. 10"
        }
      }
    }
  ]
}