Mystery books available as digital audiobooks typically come in several formats.

• Compact disc (unabridged and abridged). According to a recent survey by AudioFile magazine, the CD is the most popular format for listening to audiobooks. But it is also one of the most restrictive. A standard CD holds only about 74 minutes of audio. For most mystery audiobooks, that means an unabridged version requires multiple CDs. (Abridged versions typically require only 1.) Audiobook CDs can be played in virtually all devices that support audio CDs.

• MP3 CD (usually unabridged). MP3 is an MPEG-based, open source, compressed format that retains most of the fidelity of the original digital audio recording but requiring significantly less storage space. One disadvantage of MP3 CDs is that not all CD players support playback of MP3 files, though most players sold over the past couple of years do. As a result, only about 20% of buyers currently prefer MP3 CD audiobooks but this number is rapidly growing.

• Digital download. The digital download of audiobooks has enjoyed a recent rise in popularity. Once an audiobook has been downloaded, it can be transferred to most handheld devices, including the Apple iPod. This flexibility and the fact that digital downloads are typically less expensive than CD-based audiobooks and are available immediately upon purchase make this the ideal format for many listeners.

Digital Audio Mysteries for September 2010

Below is a selection of new digital audio mystery books available this month; for more books, visit the Mystery and Thriller audiobook page on Amazon.com.

Bad Blood by John Sandford. Virgil Flowers (4th). Audio format: Unabridged CD-ROM. Also available: Hardcover.	Wicked Appetite by Janet Evanovich. Diesel (1st). Audio format: Unabridged CD-ROM. Also available: Hardcover.	Don't Blink by James Patterson. Non-series. Audio format: Unabridged CD-ROM. Also available: Hardcover.
Dexter is Delicious by Jeff Lindsay. Dexter Morgan (4th). Audio format: Unabridged CD-ROM. Also available: Hardcover.	Bury Your Dead by Louise Penny. Armand Gamache (6th). Audio format: Unabridged CD-ROM. Also available: Hardcover.	Santa Fe Edge by Stuart Woods. Ed Eagle (4th). Audio format: Unabridged CD-ROM. Also available: Hardcover.