Editing PlainTalk (section)

====Technology====
Apple's text-to-speech uses [[diphone]]s. Compared to other methods of synthesizing speech, it is not very resource-intensive, but limits how natural the [[speech synthesis]] can be. [[American English]] and [[Spanish language|Spanish]] versions have been available, but since the advent of Mac OS X, Apple has shipped only American English voices, relying on third-party suppliers such as Acapela Group to supply voices for other languages (in OS X 10.7, Apple licensed a lot of third-party voices and made them available for download within the Speech control panel).

An [[application programming interface]] known as the Speech Manager enables third-party developers to use speech synthesis in their applications. There are various control sequences that can be used to fine-tune the intonation and rhythm. The [[loudness|volume]], [[tone of voice|pitch]] and rate of the speech can be configured as well, allowing for singing.

Input to the synthesizer can be controlled explicitly using a special [https://developer.apple.com/library/mac/documentation/UserExperience/Conceptual/SpeechSynthesisProgrammingGuide/Phonemes/Phonemes.html phoneme alphabet].