The Compendium of Kāśyapa 8.6.42

8.6.42

vindan nānāvikalpaiśca grāmarāgāṃśca darśayet
svaramaṇḍalatattvajño vikalpairbahuvistaraiḥ

and, knowing varied permutations, demonstrates the scales and melodies, / knowing the truth of the musical scale through widely expanded permutations;