-24 LUFS

Technical Foundations

-24 LUFS is the global standard for Broadcast Audio and is defined by the ITU-R BS.1770-4 Recommendation. This standard was introduced by the International Telecommunication Union to ensure consistent loudness across television broadcasters, radio stations, and professional audio channels.

Why -24 LUFS for Broadcast?

The -24 LUFS standard is more conservative than streaming (-14 LUFS) because:

1. Viewer Protection: Sudden loudness fluctuations are disruptive
2. Regulatory Requirement: Legally mandated in many countries
3. Hybrid Environments: Commercials, news, and entertainment must have equal loudness

Standards and Platforms

Workflow for Broadcast Mastering

Phase 1: Delivery

• Stereo track or surround mix with at least -6 dB headroom
• Peak meter check (not exceeding -3 dBFS)

Phase 2: Loudness Analysis

• Use broadcast loudness meter (Waves WLM Plus, iZotope RX)
• Analyze Integrated Loudness over the entire duration

Phase 3: Processing

• Multiband Compressor: Gentle compression only in problematic frequency ranges
• Master Compressor: Ratio 1.5:1 – 2:1, generous attack/release
• Limiter: Ceiling at -2.5 dBFS

Phase 4: Calibration

• Target: Between -24.5 and -23.5 LUFS
• True Peak below -2.0 dBFS
• Save metering graphs as proof

Common Mistakes

• Confusion with Streaming: -14 LUFS does not work for broadcast
• Overly Aggressive Compression: Dialogue loses naturalness
• Insufficient Peak Control: True Peak must be below -2.0 dBFS

Checklist for Broadcast Delivery

• Integrated Loudness: -24.5 to -23.5 LUFS
• True Peak: not exceeding -2.0 dBFS
• All spoken passages are intelligible
• Music retains dynamics
• Format: WAV, 24-bit, at least 48 kHz