Abstract
Mixes built from printed stems (AI-generated, source-separated, or pre-compressed bounces) measure a loudness range (EBU Tech 3342 LRA) of about 4 LU and cannot be brought into a 6–12 LU window by balance changes or section automation, because their range is uniform inside every 3-second window. This disclosure describes a pre-mastering stage that applies slow macro-dynamic expansion to the whole mix — K-weighted 3-second short-term loudness, a fixed user-selected ratio (1.5 / 1.8 / 2.2), a pivot equal to the mix's whole-song BS.1770 integrated loudness measured once, a ±4 dB clamp and a 1-second glide — offered automatically when a measured mix is under 6 LU, and reports the finding that a running-average (adaptive) pivot leaves LRA unchanged. Published to establish prior art; no rights are claimed.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Santiago, Hector, "Why AI-Generated Stems Can't Reach 6 LU, and What UNFLATTEN Does About It", Technical Disclosure Commons, ()
https://www.tdcommons.org/dpubs_series/11809