WMA Pro also offers dynamic range control using the maximum and average audio amplitudes that are calculated during the encoding process. When using 5.1 surround sound audio compressed at 384 Kbps with WMA 10 Pro, most listeners cannot discern any differences between the compressed music and the original pulse code modulation (PCM) files. WMA 10 Pro supports streaming, progressive download, or download-and-play delivery at 128 to 768 Kbps. WMA 10 Pro offers incredible quality for consumers using high-fidelity hardware and 5.1 channel surround sound-equipped computers - and for consumers playing audio content on their mobile devices. Windows Media Audio 10 Professional (WMA 10 Pro) is the most flexible Windows Media audio codec available – supporting profiles that include everything from full-resolution 24-bit/96 kHz audio in stereo, 5.1 channel, or even 7.1 channel surround sound, to highly efficient mobile capabilities at 24 Kbps to 96 Kbps for stereo, and 128 Kbps to 256 Kbps for 5.1-channel sound. 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. 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. 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. 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. The resulting sound quality is 20 percent better than audio sampled with Windows Media Audio 8 at equivalent data rates. 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). Windows Media Audio Codecs Windows Media Audio 9

Windows media player 9 for mac