USA public radio broadcast (PRX) loudness spec
What a file has to measure to pass this spec, and where each figure comes from.
| Check | Required | In LC-1 |
|---|---|---|
| Integrated loudness | −24.0 ±2 LUFS | Fixed with a level change |
| True peak | −2.0 dBTP max | Limited, with audition |
Worth knowing
PRX also accepts −3 dBFS sample peak. The NPR Distribution (PRSS) standard is reported to be the same, but its own document could not be opened.
Data source(s)
- PRX, “Formatting Audio Files for Broadcast”
Figures taken from the documents above and last read on 10 October 2026, as quotes extracted from the source: confirm against the full document before relying on it.
Something incorrect with this spec? Report it to support@orjo.co.uk.