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"Wwise® is the most advanced, feature-rich interactive sound engine for games, bar none. Whether you're an indie or a multi-million dollar production, Wwise will work for you." - Audiokinetic.com

PortAudio is a cross platform, open-source, audio I/O library. It provides a very simple API for recording and/or playing sound using a simple callback function.

OpenAL Soft is an LGPL-licensed, cross-platform, software implementation of the OpenAL 3D audio API. It's forked from the open-sourced Windows version available originally from the SVN repository at openal.org.OpenAL provides capabilities for playing audio in a virtual 3D environment. Distance attenuation, doppler shift, and directional sound emitters are among the features handled by the API. More advanced effects, including air absorption, occlusion, and environmental reverb, are available through the EFX extension. It also facilitates streaming audio, multi-channel buffers, and audio capture. »

RtAudio is a set of C++ classes that provide a common API (Application Programming Interface) for realtime audio input/output across Linux, Macintosh OS-X and Windows operating systems. RtAudio significantly simplifies the process of interacting with computer audio hardware. It was designed with the following objectives: