Polk I-Sonic ES2

At nearly $500, the I-Sonic ES2 is among the most expensive desktop audio systems for the iPod, and its features–which emphasize HD Radio reception and iTunes Tagging–place it in the company of premium table radios, such as those from Bose, Cambridge SoundWorks, and the like. If you aren’t a big radio listener or your favorite stations don’t have HD Radio versions–in other words, if you won’t take advantage of the unique iTunes Tagging feature–you can get similar audio quality for considerably less money.

On the other hand, if you’re a fan of radio, the I-Sonic ES2 sounds better and includes many more features, including iPod compatibility, than a number of popular (and similarly-expensive) table radios. As someone who enjoys radio now and then, I was impressed with the quality and offerings of HD Radio, and I found myself using the I-Sonic’s iTunes Tagging feature frequently. However, Tagging depends on good information from radio stations, as well as reliable transfer of that information from the station to the radio, then to the iPod, and, finally to iTunes; based on my testing, that chain isn’t yet completely reliable. When iTunes Tagging worked, it worked well, but those times made me wish it worked flawlessly all the time.–Dan Frakes