Achieve EBU R128 compliance for broadcast audio delivery

Steps

1. Understand the three key EBU R128 metrics: integrated loudness (target -23 LUFS ±1 LU for most European broadcast), loudness range (LRA, typically 5–20 LU for broadcast content), and maximum true peak level (not exceeding -1 dBTP)
2. Measure integrated loudness using a BS.1770-compliant meter that applies both the absolute gating threshold (-70 LUFS) and the relative gating threshold (-10 LU below the absolute-gated level) — these gates exclude silence and very quiet passages from the measurement
3. Check LRA after measuring — LRA uses 3-second overlapping blocks with modified gating (relative threshold at -20 LU) and reports the difference between the 10th and 95th percentile loudness levels; values outside the 5–20 LU range may indicate over-compression or extreme dynamics
4. Apply loudness normalization using a true-peak compliant gain adjustment or dynamic processing to reach -23 LUFS ±1 LU — for simple over-loud material, a gain reduction may be sufficient; for under-loud material, a make-up gain followed by limiting is typical
5. Verify maximum true peak does not exceed -1 dBTP using a true-peak meter (not a standard peak meter) — true-peak meters model inter-sample peaks by oversampling 4x or more to detect peaks that emerge after D/A conversion
6. Deliver with an EBU R128 loudness metadata tag where the delivery format supports it (e.g., BWF files include a 'LoudnessValue' chunk) so downstream systems can verify compliance without re-measuring