Polk Audio I-Sonic ES2 review: Polk Audio I-Sonic ES2

When the Polk Audio I-Sonic was released in the fall of 2006, it offered a then-unbeatable combination of features for a product in the tony "executive stereo system" genre: AM/FM radio with HD Radio compatibility; CD and DVD playback; and XM satellite radio support. Yes, the I-Sonic suffered from less-than-intuitive controls and a sky-high $600 price tag, but it did have the distinction of offering some of the best sound quality we've ever heard from a tabletop audio system. Flash forward to 2008, and Polk Audio is back with the sequel. The I-Sonic Entertainment System 2 (ES2) combines the same basic quad speaker design of its predecessor, but adds an improved control layout and varies the feature set. Gone are the disc player and satellite radio of the original I-Sonic. But in their place, the ES2 gets a built-in iPod dock and the first-of-its-kind iTunes Tagging.

At first glance, the I-Sonic ES2's curved black, silver, and gray housing could be mistaken for the first-gen model. There are a few key improvements, however. The front-panel LCD screen is far more readable: it's larger, the contrast is better, and it's angled back a bit, thus making it easier to read when adjusting the top-mounted controls. And those controls are a notable step up over the original I-Sonic as well. Fifteen buttons are arranged directly above the display, with the most commonly used--power, volume, source, and snooze/mute--appropriately oversized for easy access (though snooze could stand to be larger). The smaller buttons include time, alarm, and radio preset keys that are likely to be used with far less regularity. Alternately, you can use the included credit card remote to access the main functions as well.

The oblong box has a flattened oval footprint that's roughly 14.5 inches wide and 10 inches deep. Directly behind the button cluster is the iPod dock and headphone jack, which can be covered by a flip-down door when not in use. The rear panel includes the standard connectivity jacks: analog stereo input (for external audio sources) and output (for connection to larger stereo systems), and S-Video and composite video outs for compatible video iPods. Jacks for AM and FM antenna hookups are also provided (you can use the included ones, or string up your own). A USB port is present, too, but it's strictly for service upgrades--you can't use it to pull music from a flash drive.

Unlike the smorgasbord of options on the original I-Sonic, your listening choices on the ES2 are quite limited: either the iPod or the radio. (The third choice is any audio source you'd prefer to hook up to the auxiliary input.) The ES2 offers basic compatibility with pretty much any dockable iPod, but for the advanced features (remote control, video output), you'll need a newer model. (For a complete compatibility matrix, see this tip.) As for the radio, it delivers the standard (analog) and digital (HD Radio) flavors of AM and FM, any of which can be captured as one of 30 presets.

The alarm can be set to wake to a tone or a station preset (not the iPod). Alarm volume can be independently set, as well, so you can drift to sleep with the unit set at a soothing low volume, but have it automatically toggle up with enough power to wake you in the morning. That said, we would've liked to have seen dual alarms, not just a single. The sleep function can be set to any 15-minute increment up 90.

The Polk Audio I-Sonic ES2 is the first product to include iTunes Tagging. In theory, that feature lets you mark any song playing on an HD Radio station by pressing the "tag" key just below the LCD screen (or on the remote). Eventually, when you remove a docked iPod and resync it with your computer, you'll see a playlist under the iTunes Store tab (labeled, of course, "Tagged"). It lists the title and artist for each tagged song, and provides an easy link for more information--or to buy it on iTunes. The process works just fine--assuming the station is broadcasting an accurate data stream (not all of them do). That said, our reaction was basically "big deal." This might be really useful in a hands-free environment--such as a car--but at home, you could accomplish the same thing by leaving a pen and paper next to the radio, and just writing down songs that pique your interest. Not very high tech, to be sure, but it would get the job done just as well.

In terms of speakers and sonics, the I-Sonic ES2 is largely unchanged from the original version--and that's a good thing. It incorporates the same four-speaker design (two front, two rear) and PowerPort venting technology from the original I-Sonic. The combined result is a powerful, room-filling stereo sound with palpable bass that far exceeds what you'd expect from the I-Sonic's diminutive housing. Across a variety of genres, we liked what we heard. The jazzy strains of the Buena Vista Social Club were appropriately breathy and moody, the guitars on Creedence Clearwater Revival's familiar rockabilly beats were perfectly twangy, and the pulsing bass of Limp Bizkit's metal-charged "Nobody Loves Me" felt as if it was coming from a much larger speaker system. In fact, we'd be hard-pressed to detect any difference between the ES2's sound and that of its predecessor. Still, we were glad to see that the ES2 offers full bass and treble controls, so we could further tweak the sound to our liking.

In the end, we couldn't be more pleased with the sound quality of the Polk Audio I-Sonic ES2. But that satisfaction is tempered mightily by the product's underwhelming feature set. If the ES2 had the CD player, USB support, and network audio streaming found on the Denon S-52, the Polk system's $500 price tag would be a bit easier to swallow. Thankfully, the ES2 can fall back on its superior sound quality--it's among the best-in-class for tabletop audio systems, and easily trounces the lackluster sonics of the Denon. Indeed, discriminate listeners looking for a best-in-class iPod speaker may well find that the I-Sonic ES2 fits the bill. We only wish the features/performance trade-off didn't have to be an either/or scenario.