EDMProd FM / download.html
F13: Frequency or Phase Modulation

Retained analysis
The conceptual FM graphic shows a slow message, faster carrier and changing cycle spacing at roughly constant height. It distinguishes pitch/phase motion from amplitude modulation, but does not establish identical numerical FM and PM equations or Vital's exact scaling.
Documentation and visible configuration; not a new native audio test. Project observations are distinct from the source author's claims.
Provenance
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