Śaunaka Śikṣā 3

3

dvividhaṃ varṇajātaṃ hi svaro vyañjanameva ca
akārādisvaro jñeyaḥ kādi vyañjanamucyate

The class of speech-sounds is indeed twofold: vowels and consonants. / The vowels are known [to begin] with 'a'; the consonants are said to begin with 'ka'.