I have the good fortune of presenting a short audio clip from Chapter 3 of A Memory of Light, provided courtesy of Macmillan Audio. Let's examine the difference. You may find it fun to play the clip as you read the analysis.
Fans have awaited the resolution of the Black Tower plotline for three books. Sanderson makes use of their impatience, maintaining a slow boil, inching the plot forward slowly. Setting the mood for the Last Battle, the author continually dangles hope before the characters then yanks it away soon after. In this audio clip, Welyn’s proclamation deflates the reader’s hope that Logain will prevail over Taim. Hope is restored by the scepticism shown blatantly by Jonneth, or more subtly by Androl. But that scepticism must remain muted or those who express it will be crushed.
The actor’s distinct voice for each of the speaking characters in this clip makes it easy for listeners to distinguish between them, and it replaces or adds to the other tags used in the text to distinguish characters from each other. Welyn doesn’t have a Seanchan slur, or an Illianer’s distinct grammatical structure, nor does he have tag words assigned for his sole use (such as curse words for Mat, Uno, or Elayne), yet the tone and pacing of his speech are distinct from any of the other characters in the scene.
Written text retains the possibility of easily flipping back a page, or a few paragraphs, to remind yourself of a detail, or replay the conversation. Paragraph division itself helps the reader understand structural and conceptual leaps. Yet with an expressive voice, an audio presentation of the same text commands the reader's attention, adding a dimension to the story that didn't exist as a text alone. Other media such as comic book and film adaptations offer similar trade-offs, possibly altering the original vision in order to augment some particular aspect of the story. Sanderson's compact and to-the-point text lends itself well to the audio format, since he prefers to paint a cursory sketch of the locale and let the audience fill in the details. His focus on dialogue over description allows the audio presenters to take a more active role in bringing the story to life.