Tamil has a fairly complicated set of rules and variations on pronunciation, and the writing system abstracts away from the detail. Phonetic transcriptions on this page should be treated as an approximate guide, only. Many are more phonemic than phonetic, and there may be variations depending on the source of the transcription. For example, the symbol a represents a set of central sounds which may be written a, ə, or ʌ in more detailed transcriptions.
Richard Ishida, Tamil Character Notes, 23-Jun-2024, https://r12a.github.io/scripts/taml/block