The Reverberation of Sound Tantra (Tibetan: སྒྲ་ཐལ་འགྱུར, Wylie: sgra thal 'gyur), is considered to be the root tantra of the seventeen tantras of the Menngagde (esoteric Instruction) class of the Tibetan Buddhist Dzogchen tradition. These tantras are found in the Nyingma Gyubum ("The Hundred Thousand Tantras of the Ancients"), volumes 9 and 10, folio numbers 143-159 of the edition edited by Dilgo Khyentse (Thimpu, Bhutan, 1973) of the gting skyes dgon pa byang manuscript.
