What is the role of a linguist in building TTS and ASR?
Both Speech synthesis and Speech recognition are more closely related to Acoustical engineering. Until recently, Natural language processing has been almost solely within the purview of linguistics. NLP seems to have evolved being largely passive, in the sense that it was used primarily for the analytical study of language and grammar. Machine translation was likely the pivotal shift between passive to more active use of NLP, with Natural language understanding and Natural language generation being the future. NLU and NLG are all about linguistics; whereas, speech synthesis and speech recognition are more like interface tools at this point.