Following Bose’s release of SoundDock in 2004, it seemed as if every iPod speaker maker was trying to emulate or clone the company’s all-in-one iPod audio system. As of now, it looks like iPod speaker makers are instead trying to emulate or clone Bose’s Wave Radio: Cambridge Soundworks recently released the i765, and now both Polk Audio and Boston Acoustics have come out with similar options. Polk’s system, the I-Sonic ES2 ($499), follows i765’s lead in offering the equivalent of a sub-$300 audio system at a relatively huge premium, but offers several alternative features that might sway some potential customers in its direction.

Boiled down to the basics, I-Sonic ES2 is a tabletop AM/FM radio system with an integrated iPod dock and four distinguishing characteristics: it’s sharper-looking than the i765 and Wave Radio, it offers slightly better sound, plus it has both an HD Radio tuner and support for a new feature called iTunes Tagging. Discussed further in this article, iTunes Tagging lets you press a single “tag” button on the system’s face to record data about the HD Radio’s currently playing song directly to certain iPod models. You can then re-sync your iPod with your iTunes-equipped computer, find a list of songs you’ve tagged, and easily look them up on the iTunes Store for purchase.


Polk supports the system’s core functionality with a number of predictable but welcome pack-ins. There are the standards—a set of six matching iPod Dock Adapters, an Infrared remote control, and a power supply—plus three different radio antennas. One is a large hard plastic O-ring for the AM radio, while the other two are swappable cables for the FM radio. You’re supposed to test the antennas in your location to determine which works better to pick up local broadcasts; a dipole antenna can be connected rather than the single-pole one that most iPod FM radios include. Polk doesn’t include other audio or video cables, but the ES2 does have both standard audio and composite-/S-Video-out ports on its rear, as well as the ability to unlock the video-out features of 2007 iPods.


Our favorite things about the I-Sonic ES2 are its cabinet design and generally competent sound. Polk has arrayed its four drivers across two curves—a soft arc in the unit’s front, and a sharper one in the back—in order to project audio in what it describes as a 360-degree listening field around the unit, enabling it to be heard, albeit with greater bass emphasis, even if you’re standing behind it in the center of a room. Putting aside the practicality of this arrangement, considering your need to mount two unsightly external antennas near the system’s back, Polk’s silver and black enclosure uses a decent blue and white screen and modern-looking cloth speaker grilles to strip the old-fashioned plastic lines and LED display from the Wave Radio; it also presents a large array of buttons on the unit’s top, but in a decidedly more thoughtful and visually pleasing way than Cambridge did with the face i765. Overall, ES2 just looks sharp—not sexy, but better than other Wave Radio-alikes we’ve seen.


Sonically, the system is about par with the better $200-$300 iPod audio systems we’ve tested, using its larger rear-firing subwoofer drivers and front-firing full-range speakers to positive effect. Polk includes bass and treble controls that we found useful in tuning the system to produce audio that from the front of the system sounded superior in balance and similar in detail to the i765’s, possessing cleaner bass when properly tweaked. Thanks to both the huge price discrepancy and additional audio performance benefits, we wouldn’t pick the I-Sonic ES2 over Logitech’s otherwise extremely similar Pure-Fi Elite, but those with bigger budgets and a taste for half-height audio systems may feel otherwise. Polk also includes a single, no frills alarm to go with its integrated clock, which puts it at an advantage relative to the Pure-Fi Elite, but a disadvantage relative to the twin-alarm i765, and virtually all of the increasingly sophisticated $100-150 dual alarm clock radios now in the iPod marketplace.


I-Sonic ES2’s single biggest potential selling point is its inclusion of an HD Radio tuner, which for the unfamiliar is a little-known recent radio receiving technology that enables users to tune not only standard, analog AM and FM radio stations, but also a relatively unpublicized collection of newer digital stations on both the AM and FM dials. You might be surprised to realize that there are already stations broadcasting in HD Radio format: as of today, HD Radio’s web site showed 13 stations with 24 HD broadcasts in our immediate area. New York City showed 25 stations with 43 HD broadcasts, and Los Angeles had 37 stations with 58 HD broadcasts; additional channels are coming soon to each market. The vast majority of the HD Radio stations are FM channels; a minority are AM. In our local market, only one AM station offers an HD signal.


HD Radio stations are supposed to sound better than analog AM or FM radio stations, and offer existing broadcasters the ability to offer multiple sub-channels of programming rather than just a single channel. Consequently, it’s not unusual to find an FM station that has split its digital programming between two different genres of music, letting you hear soft rock on one channel and oldies on another. Unfortunately, the more a station splits its allocated “HD” broadcasting into sub-channels, the lower the maximum quality of the sub-channel’s audio goes. The result of splitting is that a broadcaster with three sub-stations will be sending out audio that isn’t much different in quality from standard FM.


There are also other, bigger issues with the HD Radio functionality. First, in our testing, tuning HD Radio stations was needlessly non-intuitive and scattershot in results. Rather than just finding and adding HD stations to the standard FM or AM dials, ES2 forces you to hit a “seek” button twice to toggle the FM or AM radio into HD tuning mode, then tries to locate stations as you sweep past them on the dial. Sometimes, it found the stations listed in the HD Radio directory. Often, it didn’t. There are obviously much easier tuning solutions than this, and a $500 radio should unquestionably have incorporated one of them.


Second, the HD Radio’s reception was decidedly unimpressive, even after optimizing both ES2’s antenna type and location. Almost invariably, we found that successful tuning of an FM band HD Radio station one minute would be interrupted a minute or two later, causing ES2 to fall back to the analog FM broadcast and losing whatever data was being pushed alongside the music we had been hearing.  Though there are supposedly 24 HD broadcasts in our area, only a few stations came in without us taking the unusual step of actually holding the antenna while the system was trying to pick them up, and then, they most often disappeared from the dial when we let the antenna go. We also never succeeded in tuning in the single HD AM station that supposedly is broadcasting locally.


While it is apparent that HD Radio can offer certain audio benefits over traditional AM and FM stations—the digital signal is at least a little cleaner, and either through Polk tweaking or actual broadcasting has a somewhat more dynamic, treble-bolstered presentation—our feeling was that the feature is ultimately a dud since it works so inconsistently and falls back to analog on so many stations. From what we gather, this set of experiences isn’t unusual for HD Radio users, and explains why the technology isn’t better known.


Similarly, though the iTunes Tagging feature generally works when the HD Radio is working, the radio’s tendency to lose the digital signal inhibits the tag button’s performance, as a song’s data blanks out when the radio falls back to analog. There are, of course, other issues. If anything, consumers would want to record songs, not tags, from the radio to their iPods; tags seem like a compromise designed to appease the music industry and accommodate HD Radio’s less than completely reliable digital signal. While we can understand this, there’s no question that the feature isn’t exactly what iPod users have been asking for. Then there’s the fact that Tagging currently works only with the fifth-generation iPod, iPod classic, and third-generation iPod nano—not the iPod touch, or older iPods. If your iPod isn’t supported, ES2 will store up to 50 tags in its own database, awaiting synchronization with a compatible iPod; without one of those models, the feature is basically useless.


All in all, while the I-Sonic ES2 delivers pretty good sound in a conservatively attractive enclosure, its $499 price tag is ultimately not justified by its features. Just as with the i765, you’re paying a premium of $200 or more over the cost of a comparably equipped audio system to gain one major benefit—here, an HD Radio tuner rather than an integrated DVD and CD player—and that feature is inhibited by performance and interface issues that detract substantially from its potential appeal. iTunes Tagging isn’t a bad idea, but it’s not a great one, either, and its reliance on both HD Radio and a limited array of supported iPods make it less attractive than it might have been. Consequently, we consider the I-Sonic ES2 to be an interesting toy for early adopters with wallets capable of funding audio experimentation, but this isn’t an all-in-one system for the masses. The same system without HD Radio and a commensurately lower price tag would have been a smarter product.


Our Rating

Limited Recommendation

Company and Price

Company: Polk Audio


Model: I-Sonic ES2

Price: $499

Compatible: iPod 4G*, 5G, classic, mini*, nano*, touch*