This audio format is used in QuickTime (iTunes) and MPEG-4 ISO files. For playback as part of a multimedia files (ie. .mpg or .m4v) all you need is the AAC decoder. For playing back stand-alone AAC files you also need the AAC parser.
As an alternative to downloading this standalone solutions, try ffdshow-tryouts which has complete support for AAC and many other codecs.
File size: 187,726 bytes, version: 1.0b9
File size: 58,187 bytes
File size: 422,136 bytes, version: 1.7
AAC - Advanced Audio Coding was added to MovieCodec.com by Bjarne (03-09-2011).