NW-S13

The NW-S13 is a compact S Series Network Walkman that effectively replaced the E Series. It offers 4 GB storage supporting MP3, WMA, AAC, and WAV playback with a lithium-ion battery rated for 77 hours. Bluetooth, video and photo playback, and Clear Phase were included.

The S13 is important because it shows the S Series taking over the role that had once belonged to the E Series. By this point Sony no longer needed both lines to do the same job, so the S family shifted closer to simple everyday Walkman territory while keeping slightly better battery life and a little more polish. It marks a handoff inside the lineup, where the S line stopped being the old feature-richer middle branch and became the practical mainstream compact one instead.