XAudio2 is a cross-platform audio API for Xbox 360

Xbox 360

The Xbox 360 is the second video game console produced by Microsoft and the successor to the Xbox. The Xbox 360 competes with Sony's PlayStation 3 and Nintendo's Wii as part of the seventh generation of video game consoles...

 and Microsoft Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

, intended as the replacement for DirectSound

DirectSound

DirectSound is a software component of the Microsoft DirectX library for the Windows operating system. DirectSound provides a low-latency interface to the sound card driver and can handle the mixing and recording of multiple audio streams....

.

The RTM version of the XAudio 2 library is included in the March 2008 DirectX SDK. The target platforms include Windows XP

Windows XP

Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...

, Windows Vista

Windows Vista

Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...

 and the Xbox 360.

Microsoft has been actively pushing developers to migrate new applications to equivalent Xbox360 audio APIs such as XAudio2 and the Cross-platform Audio Creation Tool (XACT). The XACT engine is a high-level audio programming library that operates through XAudio API on the Xbox, as a DirectSound pass-through on Windows XP

Windows XP

Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...

, and directly on the low-level audio renderer (WASAPI) in the new audio stack on Windows Vista

Windows Vista

Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...

.

Features

XAudio 2 provides low-level mixing and signal processing

Audio signal processing

Audio signal processing, sometimes referred to as audio processing, is the intentional alteration of auditory signals, or sound. As audio signals may be electronically represented in either digital or analog format, signal processing may occur in either domain...

 for high-level audio APIs such as XACT, and X3DAudio is an abstracted math-driven spatialization helper library that can be replaced by custom 3D behaviors. Some of XAudio2 features are:

• Separation of sound data from “voice”
• Submixing (arbitrary levels and routings)
• Multi-rate processing
• Per-voice filtering (built-in, in addition to programmable DSP effects)
• Programmable voices
• Effects processing, Sample rate conversion
  Sample rate conversion
  Sample rate conversion is the process of converting a signal from one sampling rate to another, while changing the information carried by the signal as little as possible...
  
   (SRC)
• Software DSP
  Digital signal processing
  Digital signal processing is concerned with the representation of discrete time signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing...
  
  
• Enhanced surround sound
  Surround sound
  Surround sound encompasses a range of techniques such as for enriching the sound reproduction quality of an audio source with audio channels reproduced via additional, discrete speakers. Surround sound is characterized by a listener location or sweet spot where the audio effects work best, and...
  
   (multichannel) and explicit multichannel panning
  Panning (audio)
  Panning is the spread of a sound signal into a new stereo or multi-channel sound field. A typical physical recording console pan control is a knob with a pointer which can be placed from the 8 o'clock dial position fully left to the 4 o'clock position fully right...
  
  /mapping dynamically to any speaker
• Native compressed data support
  • XMA on Xbox 360
    Xbox 360
    The Xbox 360 is the second video game console produced by Microsoft and the successor to the Xbox. The Xbox 360 competes with Sony's PlayStation 3 and Nintendo's Wii as part of the seventh generation of video game consoles...
    
    
  • ADPCM and xWMA (Windows Media Audio
    Windows Media Audio
    Windows Media Audio is an audio data compression technology developed by Microsoft. The name can be used to refer to its audio file format or its audio codecs. It is a proprietary technology that forms part of the Windows Media framework. WMA consists of four distinct codecs...
    
    bitstream format in a lightweight wrapper) on Windows
  • Extensible
• 3D audio handled as a separate replaceable library: XAudio 2 takes multichannel speaker volumes and X3DAudio library transforms source/listener coordinates into speaker volumes and other synthesis parameters