Microsoft Sam

The Microsoft text-to-speech voices are speech synthesizers provided for use with applications that use the Microsoft Speech API (SAPI) or the Microsoft Speech Server Platform. There are client, server, and mobile versions of Microsoft text-to-speech voices. Client voices are shipped with Windows operating systems; server voices are available for download for use with server applications such as Speech Server, Lync etc. for both Windows client and server platforms, and mobile voices are often shipped with more recent versions of Windows Phone. Windows 10 also brings the mobile text to speech voices to the desktop starting with the Anniversary Update.

Microsoft Sam is the default text-to-speech male voice in Microsoft Windows 2000 and Windows XP. It is used by Narrator, the screen reader program built into the operating system.

Microsoft Mike and Microsoft Mary are optional male and female voices respectively, available for download from the Microsoft website. Michael and Michelle are also optional male and female voices licensed by Microsoft from Lernout & Hauspie, and available through Microsoft Office XP and Microsoft Office 2003 or Microsoft Reader.

There are both SAPI 4 and SAPI 5 versions of these text-to-speech voices. SAPI 4 voices are only available on Windows 2000 and later Windows NT-based operating systems. While SAPI 5 versions of Microsoft Mike and Microsoft Mary are downloadable only as a Merge Module, the installable versions may be installed on end users' systems by speech applications such as Microsoft Reader. SAPI 4 redistributable versions are downloadable for Windows 9x, although no longer from the Microsoft website.

Microsoft Sam, Microsoft Mike and Microsoft Mary can be used on Windows Vista and later with a third-party program (like Speakonia and TTSReader) installed on the machine that supports these operating systems, however, the speech patterns differ from the Windows XP versions of these voices. In addition, LH Michael and LH Michelle can work on Windows 7 and later if speakonia and the SAPI 4 version of the voices in British English is downloaded. Microsoft Sam is the default voice for Windows 2000 and XP.

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