The 256MB MP-100 from Jens of Sweden packs considerable punch into a bite-size package at a fair price ($199). This ultracompact plug-in MP3 player has the small size, the light carriage, and the robust features to put a serious dent in the competition, although we prefer the updated version of the product, the MP-110, which has a sturdier design.
The MP-100 comes in a stainless-steel cylinder; open it up, and out pops a silver device roughly the size of a packet of chewing gum. While the MP-100 lacks the elegance of the sleek Philips MP3 Key Ring, it's about the same size (3.1 by 1 by 0.6 inches) and almost as light (1.4 ounces). One thing you won't find on most plug-in players is a screen. The MP-100 has a backlit, 128x34-pixel LCD that shows lots of information: track, artist, and album name, along with elapsed and total time, track number, battery life, and volume level. Next to the play/pause/power button on the bottom of the player is a jog dial that lets you skip tracks, adjust the volume, and navigate menus. Transferring music to the MP-100 is a simple matter of plugging the player into your system's USB port, then dragging and dropping your music files onto the player. The MP-100 works with systems running Windows 98 SE and later, Mac OS 8.6 or later, and Linux OS.
The player doesn't skimp when it comes to extras. The unit boasts an FM radio with 15 presets, and depending on the sound-quality setting you choose, it can record up to 17 hours of radio to a WAV file. Finally, the built-in mike records voice memos between 3 and 17 hours (again, depending on the quality setting) in length. Optional extras include two cases, an armband, and a portable travel charger (220V only).
Sound quality on the MP-100 was excellent, thanks to its equalizer and a signal-to-noise ratio of 90dB. Plus, it outputs enough power for most listeners: 7mW per channel at 16 ohms. Armed with nine presets (including Rock, Pop, Techno, and Jazz) and a user-defined mode, the EQ lets you tweak sound to your liking.
The lithium-polymer battery charges via USB and lasts up to an impressive 14 hours at a stretch.
While the MP-100 isn't the sexiest MP3 player we've seen, this small wonder mocks the competition by combining decent sound quality and high-end features in a compact, plug-in design.