OpenAL
OpenAL is a cross-platform 3D audio API appropriate for use with gaming applications and many other types of audio applications. ALUT is the OpenAL utility toolkit, a library providing additional functions to work with OpenAL.
Website: http://www.openal.org
Platforms supported: Win32, Linux
Headers to include: AL/al.bi, AL/alut.bi
Header version: OpenAL 1.13, ALUT 1.1.0
Examples: in examples/sound/OpenAL/