Sustainability of Digital Formats
 Planning for Library of Congress Collections

Format Description Categories >> Browse Alphabetical List>> Back

Identification and description

Full name	Audible.Com MP3
Description	Audible.Com wrapper containing an MP3 encoded bitstream. Audible.Com is a seller of recorded sound products, ranging from talking books to archived radio programs, e.g., Car Talk.
Production phase	Used for final-state, end-user delivery.
Relationship to other formats
Subtype of	AudCom, Audible.Com File Format
Contains	MP3_ENC, MP3 Encoding

Local use

LC experience or existing holdings	None
LC preference	General preference for recorded sound is WAVE_LCPM. For compressed audio, MP3_FF is preferred to AudCom_MP3; within the Audible.Com family, however, AudCom_MP3 is preferred to other encodings.

Sustainability factors

Disclosure	Not documented
Documentation	See AudCom, Audible.Com File Format
Adoption	See AudCom, Audible.Com File Format
Licensing and patents	See AudCom, Audible.Com File Format
Transparency	See AudCom, Audible.Com File Format
Self-documentation	See AudCom, Audible.Com File Format
External dependencies	See AudCom, Audible.Com File Format
Technical protection considerations	See AudCom, Audible.Com File Format

Quality and functionality factors

Sound
Normal rendering	Good support.
Fidelity (high audio resolution)	Good
Multiple channels	Apparently not
Support for user-defined sounds, samples, and patches	No
Functionality beyond normal rendering	Not investigated

File type signifiers

Tag	Value	Note
Filename extension	aa	See AudCom, Audible.Com File Format
Internet Media Type	See note.	See AudCom, Audible.Com File Format
Magic numbers	See note.	See AudCom, Audible.Com File Format

Notes

General
History

Format specifications

• See Disclosure under Sustainability factors.

Useful references

URLs

• Audible.Com (http://www.audible.com).
• Discussion of formats (http://www.audible.com/formats). At Audible.Com Web site.