{
  "batch": "Audio Letters 36–40",
  "date": "2026-11-10",
  "source_zip": "Dr-Peter-Beter-HQ 04.zip",
  "source_zip_sha256": "29479ad9beaef9e717854f2b2aa7ae554f1bba63ace7912674bf7f322de0ebba",
  "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": 16308.871836734694,
    "decoded_duration_hms": "04:31:49",
    "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": -5.7,
    "output_true_peak_dbtp_max": -3.5
  },
  "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-36-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 36 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-36-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-36-Part-01.mp3",
      "output_filename": "PDB_AL-36-P01_Restored_v2.mp3",
      "source_sha256": "32e14e9a36dabf55f7d577e4dcb2e3e849f8b6472dce38de651c81bfdbfcac77",
      "source_bytes": 19307381,
      "output_sha256": "d90e3ca473d279db1d75a4254ffba7583727e969faa2adf72f378f9a3f417e54",
      "output_bytes": 28156310,
      "source_metrics": {
        "integrated_lufs_mono": -18.5,
        "lra_lu": 3.3,
        "true_peak_dbtp": -5.9,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.886196,
        "rms_dbfs": -18.407638,
        "samples": 77583744,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.2685714285715
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.5,
        "lra_lu": 3.3,
        "true_peak_dbtp": -4.6,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -4.593641,
        "rms_dbfs": -18.43986,
        "samples": 77583744,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.2685714285715
      },
      "gain_db": -0.5,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 3.3,
        "true_peak_dbtp": -5.5,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -5.53337,
        "rms_dbfs": -19.385551,
        "samples": 77583744,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.2685714285715
      },
      "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": "7dad2526fbd3632d0fde6ef449cb635618fc7f7f7d1395ae1c5e58c23bea2719"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 36",
          "track": "1/2",
          "date": "2007"
        }
      }
    },
    {
      "id": "AL-36-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 36 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-36-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-36-Part-02.mp3",
      "output_filename": "PDB_AL-36-P02_Restored_v2.mp3",
      "source_sha256": "6003ebb292400eb6243627a489dc07838f6a69b1443d97300fd7d0141dd3063e",
      "source_bytes": 18896133,
      "output_sha256": "ca099bf44ccb9ffb3ba3e31613bc67b8665afcf4712d6df12246f4114bde0a43",
      "output_bytes": 28156728,
      "source_metrics": {
        "integrated_lufs_mono": -18.2,
        "lra_lu": 2.9,
        "true_peak_dbtp": -5.8,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.794038,
        "rms_dbfs": -18.783701,
        "samples": 77584896,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.294693877551
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.2,
        "lra_lu": 2.9,
        "true_peak_dbtp": -4.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.036991,
        "rms_dbfs": -18.808916,
        "samples": 77584896,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.294693877551
      },
      "gain_db": -0.8,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.9,
        "true_peak_dbtp": -5.3,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.280349,
        "rms_dbfs": -20.05453,
        "samples": 77584896,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1759.294693877551
      },
      "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": "75086b6d658ef91654d97642e696f79d0d9dfed39494728f612e23e0f42fe7e5"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 36",
          "track": "2/2",
          "date": "2007"
        }
      }
    },
    {
      "id": "AL-37-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 37 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-37-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-37-Part-01.mp3",
      "output_filename": "PDB_AL-37-P01_Restored_v2.mp3",
      "source_sha256": "31cdd8e6f9364dca46fdbe189a78d413fdc559d469de59ef7d840817ddbd58ce",
      "source_bytes": 17423725,
      "output_sha256": "85865db7898fddd9a95115afe14822e077988d174a3104dd9ddafee98a60b926",
      "output_bytes": 24782125,
      "source_metrics": {
        "integrated_lufs_mono": -19.2,
        "lra_lu": 2.9,
        "true_peak_dbtp": -5.8,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.797249,
        "rms_dbfs": -19.406738,
        "samples": 68283648,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1548.3820408163265
      },
      "clean_metrics": {
        "integrated_lufs_mono": -19.2,
        "lra_lu": 2.9,
        "true_peak_dbtp": -3.2,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -3.227129,
        "rms_dbfs": -19.433105,
        "samples": 68283648,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1548.3820408163265
      },
      "gain_db": 0.2,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.9,
        "true_peak_dbtp": -3.5,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -3.466611,
        "rms_dbfs": -19.678545,
        "samples": 68283648,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1548.3820408163265
      },
      "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": "8e728bc8bd8e143218122e7bd6bede2c39b2d42dd85bcdb93c3e584ffe81e255"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 37",
          "track": "1/2",
          "date": "2007"
        }
      }
    },
    {
      "id": "AL-37-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 37 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-37-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-37-Part-02.mp3",
      "output_filename": "PDB_AL-37-P02_Restored_v2.mp3",
      "source_sha256": "dfc43fb8d60afb12aca72b846d35fcf9fe9d8cb2134efcf035ac04fff061ad98",
      "source_bytes": 17948323,
      "output_sha256": "686a387f33849ed08445db61e21393844a6cbfc0d7429e417cda764e8398c1d3",
      "output_bytes": 25673632,
      "source_metrics": {
        "integrated_lufs_mono": -18.8,
        "lra_lu": 2.8,
        "true_peak_dbtp": -5.8,
        "dc_offset": -1e-06,
        "sample_peak_dbfs": -5.822371,
        "rms_dbfs": -19.364287,
        "samples": 70740864,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1604.1012244897959
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.9,
        "lra_lu": 2.8,
        "true_peak_dbtp": -4.8,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.795159,
        "rms_dbfs": -19.382669,
        "samples": 70740864,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1604.1012244897959
      },
      "gain_db": -0.1,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 2.8,
        "true_peak_dbtp": -5.3,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.346622,
        "rms_dbfs": -19.928258,
        "samples": 70740864,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1604.1012244897959
      },
      "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": "27842ee627ad3c3e44a9fa198fce8244d78c3f69bcf2f986866a9288f314b433"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 37",
          "track": "2/2",
          "date": "2007"
        }
      }
    },
    {
      "id": "AL-38-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 38 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-38-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-38-Part-01.mp3",
      "output_filename": "PDB_AL-38-P01_Restored_v2.mp3",
      "source_sha256": "0f9c31eaa6de7ba1574472521d9836acfa43b2e74e556dbefa7984f2591f82d3",
      "source_bytes": 17028677,
      "output_sha256": "e610f5828f58ebb727c118c7b74172468f66a385de18d02f6af1b572a4027710",
      "output_bytes": 24675082,
      "source_metrics": {
        "integrated_lufs_mono": -19.6,
        "lra_lu": 2.9,
        "true_peak_dbtp": -5.9,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.916715,
        "rms_dbfs": -19.738731,
        "samples": 67988736,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1541.6946938775511
      },
      "clean_metrics": {
        "integrated_lufs_mono": -19.6,
        "lra_lu": 3.0,
        "true_peak_dbtp": -4.9,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.913144,
        "rms_dbfs": -19.754635,
        "samples": 67988736,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1541.6946938775511
      },
      "gain_db": 0.6,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 2.9,
        "true_peak_dbtp": -4.8,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.755995,
        "rms_dbfs": -19.600167,
        "samples": 67988736,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1541.6946938775511
      },
      "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": "f897f75966319f28568162feeea1955153ba9a65eaef506803fc69c1ac64b5a1"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 38"
        }
      }
    },
    {
      "id": "AL-38-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 38 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-38-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-38-Part-02.mp3",
      "output_filename": "PDB_AL-38-P02_Restored_v2.mp3",
      "source_sha256": "00afb28374ed64f104bd60a776d25a22035a5e27fcf84111e844863d8f382dfa",
      "source_bytes": 18517771,
      "output_sha256": "92e7261c8fc15fdf5af577d705f7d610f39194132ee2eb7b141cdc79506ade4f",
      "output_bytes": 26645341,
      "source_metrics": {
        "integrated_lufs_mono": -17.8,
        "lra_lu": 2.7,
        "true_peak_dbtp": -5.8,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.775893,
        "rms_dbfs": -18.04362,
        "samples": 73419264,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.835918367347
      },
      "clean_metrics": {
        "integrated_lufs_mono": -17.8,
        "lra_lu": 2.6,
        "true_peak_dbtp": -4.0,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.080177,
        "rms_dbfs": -18.054447,
        "samples": 73419264,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.835918367347
      },
      "gain_db": -1.2,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 2.6,
        "true_peak_dbtp": -5.7,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -5.709056,
        "rms_dbfs": -19.699951,
        "samples": 73419264,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.835918367347
      },
      "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": "28df4cd218670e173924a57a46e85a3ed0cf32791eb02d160c9c46f58067943c"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 38"
        }
      }
    },
    {
      "id": "AL-39-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 39 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-39-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-39-Part-01.mp3",
      "output_filename": "PDB_AL-39-P01_Restored_v2.mp3",
      "source_sha256": "f6e15fd1195375b3ca9f0a85f441e0914cf430613804b5a94c68187f0e3192c6",
      "source_bytes": 18968284,
      "output_sha256": "02f9fcfd7d0f4b42c0cde1ddc70ecbca4ec5087b53c2d40e32ff9eace86bb32c",
      "output_bytes": 26639103,
      "source_metrics": {
        "integrated_lufs_mono": -18.1,
        "lra_lu": 3.5,
        "true_peak_dbtp": -5.7,
        "dc_offset": -3e-06,
        "sample_peak_dbfs": -5.675796,
        "rms_dbfs": -18.567559,
        "samples": 73401984,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.444081632653
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.1,
        "lra_lu": 3.5,
        "true_peak_dbtp": -3.5,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -3.452451,
        "rms_dbfs": -18.595437,
        "samples": 73401984,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.444081632653
      },
      "gain_db": -0.9,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 3.5,
        "true_peak_dbtp": -4.8,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.809067,
        "rms_dbfs": -19.94084,
        "samples": 73401984,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.444081632653
      },
      "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": "e49c777dff6ad8daa553d041ba89696d25a2ce5393be68240ac589d9ce016b09"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 39",
          "date": "2007"
        }
      }
    },
    {
      "id": "AL-39-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 39 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-39-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-39-Part-02.mp3",
      "output_filename": "PDB_AL-39-P02_Restored_v2.mp3",
      "source_sha256": "58412b072c310b1a0b86318166cddd2bdbbe17e8ae77259b2298319d77166a3e",
      "source_bytes": 18426246,
      "output_sha256": "cf99dc73cf8bd216ced9182271aea903aad3daa2d6b03e0c3b42b8b69cf78a2f",
      "output_bytes": 26640744,
      "source_metrics": {
        "integrated_lufs_mono": -19.0,
        "lra_lu": 3.2,
        "true_peak_dbtp": -5.9,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.87686,
        "rms_dbfs": -19.273035,
        "samples": 73406592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.5485714285714
      },
      "clean_metrics": {
        "integrated_lufs_mono": -19.0,
        "lra_lu": 3.2,
        "true_peak_dbtp": -4.5,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.500677,
        "rms_dbfs": -19.292692,
        "samples": 73406592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.5485714285714
      },
      "gain_db": 0.0,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.4,
        "lra_lu": 3.2,
        "true_peak_dbtp": -4.9,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.953353,
        "rms_dbfs": -19.738251,
        "samples": 73406592,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1664.5485714285714
      },
      "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": "e8a1f0d7cd1ee06c8ab406bf2752c3acd0b1018ad3ea14c63346a41400af4d9d"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "composer": "Dr. Beter",
          "album": "Audio Letter No. 39"
        }
      }
    },
    {
      "id": "AL-40-P01",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 40 · Part 01 (Side A)",
      "source_filename": "Dr_Peter_Beter_AL-hq-40-Part-01.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-40-Part-01.mp3",
      "output_filename": "PDB_AL-40-P01_Restored_v2.mp3",
      "source_sha256": "16d659330a9e6594aa31964c47ad2049ebe92c0242d0f945b5d5b30117327c28",
      "source_bytes": 18104230,
      "output_sha256": "fe2e077804de15a4257b07765e8711ff88727bfa0f1c37fa70b2146d4f75d99d",
      "output_bytes": 24260445,
      "source_metrics": {
        "integrated_lufs_mono": -19.3,
        "lra_lu": 3.8,
        "true_peak_dbtp": -5.7,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.673377,
        "rms_dbfs": -20.220198,
        "samples": 66845952,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1515.781224489796
      },
      "clean_metrics": {
        "integrated_lufs_mono": -19.3,
        "lra_lu": 3.8,
        "true_peak_dbtp": -4.9,
        "dc_offset": 0.0,
        "sample_peak_dbfs": -4.885273,
        "rms_dbfs": -20.2364,
        "samples": 66845952,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1515.781224489796
      },
      "gain_db": 0.3,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 3.8,
        "true_peak_dbtp": -5.0,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.003651,
        "rms_dbfs": -20.381694,
        "samples": 66845952,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1515.781224489796
      },
      "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": "f480123034e784788fc2d5f57c2b6001df5bec8d6c5c64ca9f6a2703ca2ed4b4"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "album": "Audio Letter No. 40"
        }
      }
    },
    {
      "id": "AL-40-P02",
      "category": "audio_letter",
      "performer": "Peter David Beter",
      "label": "Audio Letter 40 · Part 02 (Side B)",
      "source_filename": "Dr_Peter_Beter_AL-hq-40-Part-02.mp3",
      "original_hq_path": "docs/Dr-Peter-Beter-HQ/Dr_Peter_Beter_AL-hq-40-Part-02.mp3",
      "output_filename": "PDB_AL-40-P02_Restored_v2.mp3",
      "source_sha256": "ee71a9c54390a52f7b159183d89290a5f4719fa07c018715fca93250de7726be",
      "source_bytes": 18583234,
      "output_sha256": "6a471208c630f6db4eb30113c02dc19c433f094850af86b5e25430a568acbb64",
      "output_bytes": 25392279,
      "source_metrics": {
        "integrated_lufs_mono": -18.9,
        "lra_lu": 3.0,
        "true_peak_dbtp": -5.9,
        "dc_offset": -1e-06,
        "sample_peak_dbfs": -5.872576,
        "rms_dbfs": -19.597582,
        "samples": 69965568,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1586.5208163265306
      },
      "clean_metrics": {
        "integrated_lufs_mono": -18.9,
        "lra_lu": 3.0,
        "true_peak_dbtp": -5.0,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.018575,
        "rms_dbfs": -19.61636,
        "samples": 69965568,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1586.5208163265306
      },
      "gain_db": -0.1,
      "gain_limited_by_peak": false,
      "output_metrics": {
        "integrated_lufs_mono": -19.5,
        "lra_lu": 3.0,
        "true_peak_dbtp": -5.6,
        "dc_offset": -0.0,
        "sample_peak_dbfs": -5.57087,
        "rms_dbfs": -20.161781,
        "samples": 69965568,
        "nans": 0.0,
        "infs": 0.0,
        "duration_seconds": 1586.5208163265306
      },
      "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": "8fd09c0f1abbda210c4c1accb181a88f9b7929bc858ffadcf4c57bb4dc6e481d"
          }
        ],
        "original_metadata_preserved": {
          "artist": "Dr. Peter Beter - hq",
          "album": "Audio Letter No. 40"
        }
      }
    }
  ]
}
