Loudness Normalisation Target Kit

Computes correct loudness targets and gain adjustments per distribution platform.

THE SILENT FAILURE. Every streaming platform normalises to its own LUFS target and simply TURNS YOUR MASTER DOWN if it is louder. Nothing errors, nothing warns. The engineer masters hot, thinks it sounds punchy, and every listener hears it quieter AND with the dynamics already crushed to get there. Separately, true peak matters on its own: a file at 0 dBFS sample peak can exceed 0 dBTP after lossy encoding and clip on playback, which never appears in the DAW meter.

Every constant is cited — ITU-R BS.1770 and EBU R128 for the measurement definitions, and each platform's own published target and true-peak ceiling. Podcast targets differ from music targets and both are included.

It REFUSES to recommend from an incomplete measurement: without true peak you cannot know whether a gain increase clips, so it reports that rather than assuming headroom. Integrated, short-term and Loudness Range are kept distinct rather than conflated.

Pure arithmetic on supplied measurements. It does not decode audio.

VERIFIED: 102 tests, 10/10 mutations caught. Every mutation was observed FAILING before the source was restored — a test never seen to fail is a decoration.

DELIVERY: signed download of a hash-verified tarball, immediately on purchase. Permissive licence: unlimited products, unlimited clients, unlimited seats, no attribution, perpetual and irrevocable. One restriction, do not republish the source as source.

Interface

What you call, and what comes back. Types and signatures only — the implementation ships with the source.

  export function evaluatePlatform(measurement: Measurement, platformId: string): PlatformEvaluation;
  export function assertPlausible(m: Measurement): void;
  export function naiveAssumeHeadroom( measurement: Measurement, platformId: string, ):;
  export function getPlatform(id: string): PlatformSpec;
  export function recommendTarget(measurement: Measurement, platformIds: readonly string[]): Recommendation;
  export function asIntegratedLoudness(lufs: number): IntegratedLoudnessLufs;
  export function asLoudnessRange(lu: number): LoudnessRangeLu;
  export function asShortTermLoudness(lufs: number): ShortTermLoudnessLufs;
  export function asTruePeak(dbtp: number): TruePeakDbtp;

  export type ClipVerdict = | { status: "clips";
  export type IntegratedLoudnessLufs = number & { readonly [integratedBrand]: true };
  export type LoudnessRangeLu = number & { readonly [lraBrand]: true };
  export type ShortTermLoudnessLufs = number & { readonly [shortTermBrand]: true };
  export type TruePeakDbtp = number & { readonly [truePeakBrand]: true };
  export type ContentType = "music" | "podcast";