This codec samples audio at 44.1 or 48 kilohertz (kHz) using 16 bits, similar to the current CD standard, offering CD quality at data rates from 64 to 192 kilobits per second (Kbps). The resulting sound quality is 20 percent better than audio sampled with Windows Media Audio 8 at equivalent data rates.
The Windows Media Audio 9 codec (WMA 9) supports variable bit rate encoding (VBR), which enables even higher quality audio at smaller file sizes by automatically varying the encoding bit rate according to the complexity of the audio data. With VBR, the encoding bit rate increases to capture complex sections of data and then decreases to maximize the compression of the less complex sections, producing compact, high-quality compression.
WMA 9 is backward-compatible with previous Windows Media Audio-compatible decoders, which means that WMA 9 content can be played with previous versions of Windows Media Player or older consumer electronic devices that support Windows Media. As with all Windows Media 9 Series codecs, it supports the Windows Media digital rights management platform, which is used to securely package and distribute copy-protected digital media.
Last modified 25th May 2010