{ "test_date": "2026-09-09", "status": "Measured rerun of the corrected build, with frozen offset 117 dB. No new correction was fitted or added to these exported measurements.", "recording": { "sample_count": 227, "hardware_model": "iPhone18,3", "operating_system": "iOS 26.6.1 (23G83)", "app_version": "1.0", "app_build": "1", "measurement_version": "a-weighting-2", "calibration_version": "niosh-comparison-2026-09-09-v1", "input_route": "iPhone Microphone", "measurement_mode_active": true, "measured_dba_minus_current_weighted_dbfs": 117, "largest_identity_error_db": 0.0 }, "comparison_scope": "The NIOSH case values are from the earlier reference pass. A complete contemporaneous NIOSH sequence was not recorded for this rerun. Differences can include source, room, geometry, and app effects; this does not identify their separate causes.", "scoring": "Original guarded late-1.8-second windows, one actual exported sample each. No interpolation or replacement sample selected around the notification.", "alignment": { "file_start_lab_elapsed_seconds": 3.0552931385431066, "clean_transition_estimates": 12, "transition_start_offset_range_seconds": [ 2.972575832575643, 3.09206769839102 ], "method": "Independent coarse matching of sync, tone-step and quiet-reset signatures, then known 1s Slow energy step timing. Notification overshoot excluded from timing estimation only.", "sensitivity_margin_seconds": 0.25, "margin_is_formal_confidence_interval": false }, "notification": { "affected_case": "T06", "stimulus": "250 Hz / -9 dB relative file level", "first_exported_spike_elapsed_seconds": 86, "first_exported_spike_source_seconds": 82.9447068614569, "maximum_recorded_slow_elapsed_seconds": 87, "maximum_recorded_slow_source_seconds": 83.9447068614569, "maximum_recorded_slow_dba": 57.8277, "raw_peak_at_first_spike_dbfs": -34.8095, "timing_limit": "1 Hz export identifies spike samples; it does not establish the exact audible onset or end. The last pre-spike sample at elapsed85 precedes the scheduled T06 onset.", "previous_case_T05_scored_before_spike": true, "T06_guarded_sample_elapsed_seconds": 94, "T06_guarded_measured_dba": 50.4872, "T06_previous_niosh_dba": 49.9, "recovery_model": { "time_constant_seconds": 1, "fit_samples_elapsed_seconds": [ 87, 88, 89, 90, 91, 92, 93, 94, 95 ], "model": "P(t)=Pbaseline+E87*exp(-(t-87)/1s), in an arbitrary linearized energy scale.", "estimated_baseline_dba": 50.43787277814451, "fit_rmse_db": 0.03698654961909212, "estimated_carryover_at_guarded_sample_db": 0.017688507307482844, "estimated_carryover_at_guarded_window_start_db": 0.04535105160947058, "sensitivity_to_tail_fit_start": [ { "fit_elapsed_start_seconds": 87, "estimated_carryover_at_scored_elapsed_94_db": 0.017688507307482844 }, { "fit_elapsed_start_seconds": 88, "estimated_carryover_at_scored_elapsed_94_db": 0.01741037873341481 }, { "fit_elapsed_start_seconds": 89, "estimated_carryover_at_scored_elapsed_94_db": 0.016924779903266275 }, { "fit_elapsed_start_seconds": 90, "estimated_carryover_at_scored_elapsed_94_db": 0.017888919676656737 } ], "caveat": "Model-based estimate of detector memory, not a precise subtraction of the notification or an acoustic uncertainty bound. All reported case values remain the actual unmodified exports." }, "downstream_maximum": { "observed_recent_maximum_dba": 66.9314, "first_exported_elapsed_seconds": 87, "last_exported_elapsed_seconds": 116, "first_lower_exported_elapsed_seconds": 117, "lower_value_dba": 59.3712, "scoring_cases_affected": [ "T06", "T07" ] }, "downstream_rolling_laeq": { "T06_guarded_window_laeq_dba": 59.5122, "T06_guarded_current_dba": 50.4872, "last_affected_window_about_elapsed_seconds": 117, "caveat": "The 30s rolling average also mixes preceding test sounds. Its total difference from the live number is not solely the notification. Exact notification-only LAeq cannot be reconstructed from 1 Hz sampled statistics." }, "handling": "Retain the original guarded sample for the direct 16-case comparison; additionally report a conservative 15-case set that excludes the entire notification-affected T06 plateau. Keep the pre-existing B00/T05 exclusions in both. No different scoring window or correction is selected to improve agreement." }, "metrics": { "original_16_case_set": { "all": { "count": 16, "mean_difference_db": -0.13434999999999997, "mean_absolute_difference_db": 0.5413249999999992, "rmse_db": 0.8099229168569059, "maximum_absolute_difference_db": 1.9063999999999979 }, "fit": { "count": 11, "mean_difference_db": -0.24964545454545375, "mean_absolute_difference_db": 0.7130090909090896, "rmse_db": 0.9651142810333619, "maximum_absolute_difference_db": 1.9063999999999979 }, "holdout": { "count": 3, "mean_difference_db": 0.2272999999999996, "mean_absolute_difference_db": 0.23243333333333283, "rmse_db": 0.28210983085788816, "maximum_absolute_difference_db": 0.3662999999999954 }, "repeat": { "count": 2, "mean_difference_db": -0.04270000000000351, "mean_absolute_difference_db": 0.06040000000000134, "rmse_db": 0.07396925036797697, "maximum_absolute_difference_db": 0.10310000000000485 } }, "conservative_15_case_set_excluding_notification_plateau": { "all": { "count": 15, "mean_difference_db": -0.1824533333333335, "mean_absolute_difference_db": 0.5382666666666656, "rmse_db": 0.8226298584418135, "maximum_absolute_difference_db": 1.9063999999999979 }, "fit": { "count": 10, "mean_difference_db": -0.3333299999999994, "mean_absolute_difference_db": 0.7255899999999983, "rmse_db": 0.9950425865258214, "maximum_absolute_difference_db": 1.9063999999999979 }, "holdout": { "count": 3, "mean_difference_db": 0.2272999999999996, "mean_absolute_difference_db": 0.23243333333333283, "rmse_db": 0.28210983085788816, "maximum_absolute_difference_db": 0.3662999999999954 }, "repeat": { "count": 2, "mean_difference_db": -0.04270000000000351, "mean_absolute_difference_db": 0.06040000000000134, "rmse_db": 0.07396925036797697, "maximum_absolute_difference_db": 0.10310000000000485 } } }, "sensitivity": { "full_two_second_original_set": { "count": 16, "mean_difference_db": -0.1405499999999993, "mean_absolute_difference_db": 0.5427062499999993, "rmse_db": 0.8112074237671886, "maximum_absolute_difference_db": 1.923499999999997 }, "full_two_second_holdouts": { "count": 3, "mean_difference_db": 0.21558333333333243, "mean_absolute_difference_db": 0.23878333333333046, "rmse_db": 0.2792250540931667, "maximum_absolute_difference_db": 0.35549999999999216 }, "maximum_active_case_change_using_two_samples_db": 0.04070000000000107 }, "four_khz": { "case_ids": [ "T11", "T12", "T13" ], "differences_from_previous_niosh_db": [ -1.9064, -1.6093, -1.6836 ], "changes_from_previous_offline_values_db": [ -0.8851, -0.8184, -0.8283 ], "interpretation": "These later 4 kHz differences are larger than in the original offline result and occur roughly a minute after the notification. The short Slow-detector tail cannot explain them. A contemporaneous reference pass is needed to distinguish possible causes." }, "repeat_first_last_dba": [ 56.4969, 56.5177 ], "limitations": [ "The earlier offline result's 1.02 dB largest difference is not the largest difference in this measured rerun; the rerun maximum is about 1.91 dB against the earlier reference.", "Held-out sounds did not influence the original correction; this rerun is additional evidence but is not independent absolute-acoustic validation.", "No full new NIOSH pass was recorded. A stable setup-noise check cannot establish an unchanged response at every frequency.", "Sampled raw peaks do not approach 0 dBFS, but the export is not an uninterrupted waveform and cannot exclude unsampled clipping." ] }