In the next few weeks Audible we will be moving all downloads to an enhanced, high-quality audio format and will no longer support format 4 downloading. Your Audible titles are yours to keep and will be available for download in the new, higher-quality audio format. If you prefer to listen to your Audible titles in format 4 audio, you will want to download them all to your device before they make the switch on June 30th.
You can continue downloading using the Audible Manager software on your computer if you would like, but you will need to make sure you are downloading in Enhanced format. If you switch to a different computer in the future, you will need to download a new software called AudibleSync, which the company is developing right now.
Audible Enhanced format is exclusive to Audible! Audiobooks in Enhanced format are minimally compressed, so their audio quality is the best on the market. What this means, however, is that the audiobook file is also very large and takes a bit more time to download. The bitrate on this format is 64kbit/s whereas Format 4 is more suited to older devices like an iPod Touch, that doesn’t have very much internal storage, the downloaded audiobook is often half the size as the enhanced format. The bitrate on this is 32kbits.
Basically, if you are listening to Audible audiobooks on 1st and 2nd-generation iPod shuffles (from 2005) and pre-2010 mp3 players you are going to be in a world of hurt, at the end of June.
Michael Kozlowski is the Editor in Chief of Good e-Reader. He has been writing about audiobooks and e-readers for the past ten years. His articles have been picked up by major and local news sources and websites such as the CBC, CNET, Engadget, Huffington Post and the New York Times.