DirectSound3D (DS3D) is an extension to DirectSound introduced with DirectX 3 in 1996 with the intention to standardize 3D audio in Windows. DirectSound3D allows software developers to utilize audio by writing once for a single audio API instead of rewriting code numerous times to work for each audio card vendor.
In DirectX 5, DirectSound3D gained the support for sound cards that use third party 3D audio algorithms in order to accelerate DirectSound3D properly, through methods approved by Microsoft.
In DirectX 8, DirectSound and DirectSound3D (DS3D) were officially merged and given the name DirectX Audio, however the API is still commonly referred to as DirectSound.
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