Test Report: Polk Audio LSiM Speaker System

History may one day judge “offshoring” to be the macroeconomic disaster that some pundits would have us believe. Still, you can’t argue that it’s been a microeconomics windfall for American consumers.

I mean, just look at these things: Polk’s new LSiM707 towers stand taller than some adults, weigh nearly 100 pounds, and incorporate five proprietary drivers — each. They’re beautifully finished with real wood veneers, are screwed together as nicely as almost any mass-produced loudspeaker you can name, and arrive loaded with proprietary driver and crossover technologies. Sure, $3,990 for the Polk pair ain’t cheap, but it’s half the cost of many domestically built equivalents.


And the 707s are just the anchor. Polk sent a full pallet of a supporting cast, beginning with the LSiM706c center channel, which shares the towers’ vertical-array, tweeter-under midrange-tweeter module, while omitting the oval “subwoofer” drivers. (Both models include Polk’s PowerPort, a tapered-cone external diffuser deployed as an anti-port-noise measure; the tower’s is down-firing, while the center’s faces rearward.) Polk touts the 706c as “the big center channel for serious listeners,” and there’s no arguing the quantifiable part: The 706c weighs some 46 pounds, is nearly a yard wide, and was barely accommodated by my low, below-the-TV center-channel stand.

Completing the lineup was an LSiM702 surround pair, a single-woofer variant in a wall-hugging, bow-front enclosure. These went on my high shelves, flanking and slightly behind the listening position.

As if this wasn’t enough, Polk threw in not one but two lily-gilders: a pair of DSW microPRO 3000 subwoofers of the modern, ultra-power/ultra-compact ilk, in this case a 10-inch design with a novel square, down-firing passive radiator. I located one sub in my established woofer home behind/outboard of the right-front speaker, and its twin roughly a third up the left-side wall. After a week’s medical leave to recover from the unboxing — a decidedly two-man job — I placed the 707s in my usual locations, about 3 feet from the front wall, and wired up their high-grade, all-metal terminals. With the center and surrounds in place, and the system balanced up with the fronts full-range and the center and surrounds both crossed over at 60 Hz, I was ready to proceed.


After my usual break-in routine — a couple weeks of low-attention, utilitarian duty — I began as always with close listening of 2-channel music via the 707s alone, operating full range. The big take-away from these sessions? The hulking Polks simply do not “sound like big speakers.”

Which I mean as high praise. The 707s effected no over-emphasis of bass, whether middling or deep; no “extra” etching of treble detail; and no breathed-upon conjuring of depth. On technically and musically excellent recordings such as a recent HDtracks 96/24 download of a Ravel string quartet by the Eroica Quartet, the Polk towers produced focused, beautifully detailed, timbrally honest music. And I could easily discern the players’ U-shaped seating via a stereo image that conveyed a nice lateral precision along with a comfortable illusion of stage depth.

More full-range music only added to the impression of effortless excellence. Pop vocals were uniformly correct, by which I mean free of narrow colorations such as honk or nasality (especially on male voices), and powerfully anchored at the mixed location without any of the vagueness or slight lateral wandering that one occasionally hears from some speakers. This was quite dramatic on Natalie Merchant’s “San Andreas Fault” (an HDtracks hi-rez file culled from her remastered Retrospective masters), on which her distinctive voice, lovingly miked and recorded as always, sounded preternaturally intimate and textured.

With regard to bass, the 707s make some. Actually, they make a lot. I kept pulling the towers farther and farther forward until I achieved what I considered an honest balance; this put the baffles nearly 6 feet from the front wall and left the speakers alarmingly close to the listening position (about 8 feet). They then sounded great for stereo listening, but it’s not a layout I could live with long-term in my studio.

Still, the 707s could be a little over-enthusiastic on the bottom octaves. A record like James Taylor’s Hourglass, an effective yardstick for bass-rich mixes, sounded superb — if you like bass, and I do. But inferior pop productions with hyped-up 50- to 100-Hz octaves, which include most mass-market R&B from the past dozen years or so, frequently sounded a little overwhelming or even a bit thuddy. By contrast, full orchestral music, which often seems a bit bass-shy to our pop-jaded modern ears, brought out the Polks’ full bloom.

On the film-sound front, a throwaway like Tower Heist (an object lesson in all that’s wrong with Hollywood) barely raised the Polks’ collective pulse, though the Ferrari-out-the-window sequence had some moments that briefly suspended this viewer’s torpor. I next tried the Tom Cruise War of the Worlds, and was immediately sucked into a fully integrated, big-theater (in truth, better) experience.

In fact, whatever disc I played sounded clear, intelligible, smooth, and big. Really, I established one beef only with the LSiM system’s surround persona. The 706c center speaker sounded admirably unchanged from virtually any practicable listening/ viewing angle. But most male speaking voices sounded distinctly fuller, or even bassier, via the center-channel unit than did the same voices heard in mono mode via the 707 towers.

Pulling the center a couple feet farther out in front of the screen seemed to make a slight improvement, and I will say that without direct comparisons I never found male dialogue objectionably or event noticeably “fat” under continuous listening.