(CNET) -- The Sony NWZ-A720 Walkman series is a subtle evolution of the NWZ-A810 series we enjoyed in 2007. This year, Sony is treating us with a larger screen and a more assertive design, offered in 4GB ($149), 8GB ($199), and 16GB ($299).
Given Sony's track record with curvy, rounded designs, the Sony NWZ-A720 is refreshingly square.
Measuring 2 inches by 3.75 inches by 0.4 inch, it has a metallic body and a 2.4-inch screen.
The NWZ-A720 is a little larger than its predecessor, but it maintains a slim, pocketable profile.
The circular four-way navigation pad found on last year's Sony NWZ-A810 has turned into a more solid-feeling square on the A720, flanked by two small option and menu buttons.
All other buttons are confined to the right side of the player, including a rocker switch for volume control and a hold switch. The bottom of the A720 Walkman features a headphone output and proprietary USB connection.
The Sony NWZ-A720 is stocked with features, including music, photo, and video playback. On the audio end of things, Sony is continuing its support for MP3, AAC, WMA, WAV, and DRM-protected subscription music files.
In typical Sony style, the restrained design of the music playback screen betrays the awe-inspiring music enhancement technology working behind the scenes, such as a 5-band EQ, Clear Bass, Clear Stereo, DSEE high-frequency restoration, and dynamic normalization.
With its 2.4-inch QVGA LCD and excellent video battery life, the Sony NWZ-A720 is the most video-worthy Walkman we've seen. Sony offers limited video format compatibility, however, including MPEG-4 and H.264 sized at a strict 320x240 ratio. Fortunately, the popularity of the iPod and video podcasts has made the QVGA MPEG-4 file format one of the most abundant on the Web.
The Sony NWZ-A720 is a solid player with plenty to brag about, but the exclusion of features such as an FM radio, voice recording, and memory expansion is worth keeping in mind as you compare the Walkman with its competition. You should also know that Sony offers an identical-looking version of this player (the Sony NWZ-A820 series) which includes built-in Bluetooth audio streaming, at an increased price.
Year after year, Sony's MP3 players demonstrate some of the highest standards for audio quality. Even at its factory setting, the Sony NWZ-A720 radiates with fidelity that just gets better as each one of its many sound-enhancement features activate.
Listening through the excellent pair of included Sony EX in-ear headphones, the rattling saxophones of Moondog's "Dog Trot" were vibrant and easy to pick out in the stereo soundstage. Renowned for its buttery bass performance, the Clear Bass enhancement EQ feature perfectly sweetened the rolling dub synth notes of Squarepusher's "Port Rhombus" with no noticeable distortion.
Videos appeared bright, crisp, and colorful on the Sony NWZ-A720. The Walkman's screen is 0.4 inch larger than the screen found on the third-generation iPod Nano, and it shares a similarly impressive pixel density and sharp picture quality. Videos can be rotated between landscape and portrait view on the Sony NWZ-A720, and audio and video files are automatically bookmarked when the player is stopped or shut down.
Sony rates the NWZ-A720's battery life at an impressive 36 hours of audio playback and 10 hours of video. We'll update this review with our CNET Labs battery results once testing is complete.
The Sony NWZ-A720 Walkman is an unquestionably great series of MP3 players, however, as a competitor to the iPod Nano it faces steep competition. Creative's Zen MP3 player, for instance, offers a larger screen, an FM radio, voice recording, and memory expansion, while Microsoft's Zune boasts coveted features such as integrated podcast management and built-in Wi-Fi.
Sony is clearly king of the hill when it comes to sound quality, but users seeking a more well-rounded MP3 player have plenty to choose from.
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