Introduction to 3-D Sound

DirectSound enables an application to change the apparent position and movement of a sound source. A sound source can be a point from which sounds radiate in all directions or a cone outside which sounds are attenuated. Applications can also modify sounds using Doppler shift.

Although these effects are audible using standard loudspeakers, they are more obvious and compelling when the user wears headphones.

This overview introduces the basic concepts of 3-D sound as implemented by DirectSound. The following topics are discussed:

• Perception of Sound Positions
• Listeners
• Sound Cones
• Distance Measurements
• Doppler Shift
• Integration with Direct3D
• Mono and Stereo Sources

Specific information on how to use 3-D sound in an application is found in the following sections:

• DirectSound 3-D Buffers
• DirectSound 3-D Listeners