Sony Walkman NWZ-S638F

Sony's NWZ-S638F arrived in 2009 as the Walkman that finally let go — no ATRAC, no SonicStage, no proprietary software requirement outside Japan. Just drag, drop, and play, straight from iTunes or Windows Explorer. The ultra-slim 7.5mm body packed 8GB of storage, a sharp 2-inch QVGA screen for photos and video, and SensMe technology that analyzed your library and sorted it into mood channels automatically. Four Clear Audio technologies handled the sound. Forty hours of battery life handled everything else.

THE LOOKS

At 89.5 × 42.9 × 7.5mm and 46 grams, the S638F is the kind of thin that makes you double-check it's actually in your pocket. The glossy finish, circular control pad, and backlit 2-inch QVGA display give it a clean, minimal look that holds up well today. The screen rotates between portrait and widescreen for video. Available in silver, black, and red — each with that late-2000s gloss that catches the light properly.

THE SPECS

8GB built-in flash memory. Supports MP3, AAC (non-DRM), WMA (DRM), MPEG-4, AVC, and JPEG. 2-inch QVGA LCD (240×320 pixels), portrait and widescreen display. FM radio, 30 station presets. 5-band equalizer, four Clear Audio technologies including Clear Stereo and Clear Bass, Dynamic Normalizer. SensMe mood-based playlist organization. 40-hour battery life, 3-hour charge time. Drag-and-drop via Windows Media Player 11, Windows Explorer, or iTunes (non-DRM). Weighs 46g.

DESIGN HIGHLIGHTS

• 7.5mm ultra-slim profile: One of the thinnest Walkmans of its generation — the kind of flat that disappears into a jacket pocket without a trace and still somehow holds 8GB and a screen.
• SensMe mood-based organization: The system analyzed your library and automatically sorted tracks into channels by energy and feel — a genuinely useful shortcut for large collections that didn't require manual playlist building.
• Drag-and-drop without proprietary software: The first S-series to drop SonicStage outside Japan, making file management as simple as moving folders — a bigger deal in 2009 than it sounds now.

THE VERDICT

The NWZ-S638F is the late-2000s Sony Walkman at its most polished and least Sony — no ecosystem lock-in, no format politics, just a beautifully slim device that plays your music and looks excellent doing it. The sound is warm and detailed with properly deep bass, the screen is sharp for its size, and 40 hours of battery life is still impressive by any standard. A sleek artifact from the last era when dedicated music players felt like a considered lifestyle choice.