Sony Walkman NWZ-S638F

Sony's NWZ-S638F arrived in 2008 as part of the company's first Walkman generation to abandon ATRAC and SonicStage requirements outside Japan, finally embracing drag-and-drop file management that made it genuinely compatible with iTunes and Windows Media Player. The ultra-slim body at just 7.5mm thick housed an 8GB flash memory, a sharp 2-inch QVGA LCD that could display photos and videos in portrait or widescreen, and Sony's new SensMe technology that analyzed and organized music by mood at the touch of a button. Four Clear Audio technologies worked together to refine the sound, while Dynamic Normalizer balanced volume levels between tracks. With 40-hour battery life and support for MP3, AAC, WMA, and video formats including MPEG-4 and WMV, it positioned itself as Sony's best effort yet to challenge the iPod nano, though reviews suggested it still lacked that final degree of excitement compared to Apple's offering.

THE LOOKS

The S638F embraces ultra-slim industrial design at 89.5 × 42.9 × 7.5mm and 46 grams. The 2-inch QVGA LCD (240×320 pixels) displays sharp videos, photos, and album art in both portrait and widescreen orientations. Available in vibrant colors including silver, black, and red with a glossy finish. Circular control pad with four-way directional buttons surrounding a central play/pause key, flanked by back and option buttons. The ultra-bright display remains visible in various lighting conditions thanks to its backlight. USB 2.0 connectivity for drag-and-drop file transfer—no proprietary software required.

THE SPECS

The S638F has 8GB built-in flash memory. Supports MP3, AAC (non-DRM), WMA (DRM), MPEG-4, AVC, and JPEG formats. 2-inch QVGA LCD (240×320 pixels) with backlight. FM radio with 30 preset stations. 5-band equalizer with digital volume control. SensMe technology for mood-based music organization. Four Clear Audio technologies (Clear Stereo, Clear Bass, etc.). Dynamic Normalizer for consistent volume. Battery life: 40 hours continuous audio playback, 3-hour charge time. Drag-and-drop compatibility with Windows Media Player 11, Windows Explorer, and iTunes (non-DRM content). Pre-loaded with 8 music videos. Voice recording function not included.

DESIGN HIGHLIGHTS

• Ultra-slim 7.5mm profile: The remarkably thin body made it one of the slimmest Walkmans of its generation, genuinely pocketable without bulk.
• SensMe mood-based music organization: The technology analyzed your music library and automatically organized songs into mood channels (Energetic, Relaxed, etc.) at the touch of a button.
• No SonicStage required—drag and drop compatibility: The first S-series to abandon Sony's proprietary software outside Japan, finally supporting direct drag-and-drop from iTunes and Windows Media Player.

THE VERDICT

The NWZ-S638F was Sony's most convincing iPod nano competitor to that point, finally abandoning the SonicStage software nightmare and embracing universal drag-and-drop file management. The ultra-slim design, sharp display, and 40-hour battery life made it genuinely competitive on paper, while the sound quality was warm and balanced with impressively deep bass that didn't compromise midrange or treble. SensMe technology for organizing music by mood was genuinely useful rather than gimmicky. However, reviews consistently noted it lacked the final degree of excitement and energy that the iPod nano offered—that visceral engagement with music that made Apple's player feel more alive. The screen was smaller than some rivals, and while sharp, the player was too compact to be a serious video device. Format support excluded OGG and FLAC, limiting audiophile appeal. Today it's a sleek artifact from the late 2000s MP3 player wars, representing Sony's best effort to match Apple before smartphones made dedicated players largely obsolete.