Audio Identifier is a FREE audio inspector. You can browse through your audio collection with it and it will show you useful information, like average bitrate, used encoder and settings, guessed quality etc.
It has Unicode support, the capability of exporting data as HTML and much, much more.
It supports many audio formats: MPEG Audio (mp3), MPEGplus (mpc), WAV (wav), TwinVQ (vqf), Ogg Vorbis (ogg), Windows Media Audio (wma), AAC (aac), Speex (spx), Monkey's Audio (ape), WavPack (wv), FLAC (flac),
TrueAudio (tta), OptimFROG (ofr), AC3 (ac3) and DTS (dts).