Cuttin-Edge, On-the-Spot Reporting

Polk Audio has significantly redesigned their top-of-the-line LSi series of loudspeakers and dubbed them LSiM. Even with all of the new upgrades, the price of a pair of bookshelf speakers starts at only $1500 and goes up to $4000 for a pair of their largest floorstanders.

The new LSiMs feature advanced drivers such as a ring-radiator tweeter coupled to a small 3.25" midrange driver to form what Polk calls a Dynamic Sonic Engine. A larger 5.25" or 6.5" (depending on the model) midrange-woofer driver is also utilized, along with oval-shaped woofers in the floorstanders. The floorstanders are true four-way loudspeakers, and the bookshelf is a three-way design.

polk_bookshelf

The cabinets are heavily braced, and each driver in the largest M707 tower has its own chamber for a total of five separate compartments. Even the grille has been designed to reduce diffraction by being only 1mm thick. The grille mounts flush to the cabinet with magnets.

polk_grille

The entire line consists of the M707 and M705 towers, M703 bookshelf, M706C and M704C center-channels, and the M702FX surrounds. Even though they've been significantly improved, the new LSiM models are priced only slightly above the LSi models that they replace.

polk_floorstander

Listening to the largest floorstander, the M707, powered by Audio Research and Wadia electronics, I found that the sound was astonishingly clear and lifelike with tons of tightly controlled subterranean bass on the Patriot Games soundtrack. This was not the best speaker that I heard at the Venetian this year, but after hearing many of Polk's much more expensive competitors, I found it hard to believe how close the LSiMs are to the competition at a fraction of the price.

Roger Kanno
Contributor, The SoundStage! Network