Cracking the New GRE 2012 Graduate School Test Preparation Ser. by Princeton Review Staff Revised Copyright Year: 2011 ISBN-13: 9780375428180 Available format(s): Classic Audio Add to Bookshelf What's an Audio Format Audio format refers to the way an audiobook is recorded. Not all audiobooks have the same formats. Classic Audio: A human reading an audiobook without the text displayed. VOICEtext (H): Human narrator with text that you can follow along with as it reads. VOICEtext (S): Synthetic voice with text you can follow along with as it reads.