Q: I am seeing a lot of references to eAAC and eAAC+ in cell phone test reviews, notably for Sony Ericsson phones. I use AAC for my iPod, but I’m interested in these other formats. Can you elaborate on what eAAC and eAAC+ actually are? Does my iPod or iTunes support them?
A: The eAAC and eAAC+ codecs are evolutions of the current AAC codec, allowing for even smaller files at excellent sound quality levels. They achieve this in part by the use of a technology called “Parametric Stereo”, which combines the left and right channels of audio for greater compression, but in a special way that allows the stereo separation to be restored for playback.
You’re right – at this point, the codec has currently only appealed to cell phone manufacturers and over-the-air music stores, as their needs for low-bitrate music are clearly more urgent than manufacturers of large-capacity hard drive players.
Years ago, there were rumors of Apple’s plans to incorporate the codec into the iTunes/iPod/Quicktime/Music Store system, but this still hasn’t materialized.
Still, more efficient codecs are a natural progression of audio technology, and especially with Apple’s rumored entry into the cell phone market with its “iPhone,” updated AAC technology may find its way to iTunes in the near future.