# XM Improves Its Sound



## Steve Mehs (Mar 21, 2002)

On Thursday, XM Satellite Radio unveiled its state-of-the-art digital sound technology, featuring customized "CT-aacPlus" audio encoding with Neural Audio optimization, which the company said provides superior sound quality resembling a CD.

The key to the new XM sound is CT-aacPlus, a third-generation audio encoding technology. CT-aacPlus is the combination of Advanced Audio Coding (AAC), a standard combining the work of experts big on perceptual audio encoding - AT&T, Dolby, Fraunhofer and Sony - with Coding Technologies' Spectral Band Replication (SBR) technology.

As a combination of AAC and SBR, CT-aacPlus has been tested by high-profile audio experts from around the world. Double-blind listening tests conducted by the BBC, Deutsche Telekom and others have established that the CT-aacPlus combination is more than 30 percent more efficient than AAC, thereby providing superior sound quality at satellite radio bit rates compared to any other audio coding technology.

Based on the test results, CT-aacPlus has been adopted by International Digital Radio Mondiale consortium and accepted by MPEG as the "reference model" for the upcoming version of MPEG-4.

In another move at the company, XM closed on its public offering of 13.4 million common shares at a price

From SkyReport (Used with permission)


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