OTHER TECH

The biggest challenge facing most people installing a surround system (after approval from the spouse!) is the wiring. Getting wire from your component stack to the surround speakers in the back of the room can be especially challenging.

As a custom installer, I get asked repeatedly if there's a wireless speaker that will solve the problem. The sound quality of most wireless speaker systems is better suited to background listening, and they really aren't designed for home theater. But the Kenwood RFU-6100 900-MHz transmitter/receiver combo is designed for home theater and lets you use your own speakers.

SETUP AND BASIC OPERATION Installation is about as easy as it gets: you connect the transmitter to your A/V receiver and the even smaller RFU-6100 receiver to your surround speakers. The transmitter trails a pair of nearly 4-foot speaker wires that connect to your A/V receiver's left and right surround-channel outputs. (It's too bad the cabling can't be upgraded, because it's very thin - 20-gauge.) The transmitter is powered by a supplied 15-volt DC power supply that plugs into any wall outlet. The receiver, which incorporates a 50-watt-per-channel stereo amplifier to drive the surround speakers, plugs directly into an AC outlet. It has spring-clip speaker terminals that accept bare wire as thick as 14-gauge.

The manual suggests using an A/V receiver rated around 100 watts per channel, but not exceeding 120 watts, so I used a Denon AVR-3805 rated at 110 W x 7. It lets you switch between two separate pairs of left/right surround speakers, so I connected the Surround A terminals directly to the speakers and the B terminals to the Kenwood transmitter. This allowed me to adjust and match levels and quickly switch between the receiver and the Kenwood. Balancing the speakers - two pair of B&W DM601s - on both amps proved that the receiver was the obvious power champ. The Denon-powered channels had to be set 2.5 dB lower than the Kenwood's.

PERFORMANCE While Kenwood specs the transmitter range as 100 feet, real-world results will vary, and as with any wireless device, placement is crucial. I first connected the system at the showroom where I work, with the units about 20 feet apart, and had no real issues. At my home, however, with about a 30-foot spread, I had to deal with quite a bit of interference, moving the transmitter and receiver until the loud pops and static disappeared. Unfortunately, interference wasn't the only noise I heard. Driven by the receiver without a program signal, the B&W speakers were virtually silent, but under the same conditions the Kenwood produced a clear hiss from the tweeter and a hollow ear-to-seashell sound from the woofer with my ear up close to the drivers. The noise was inaudible from the listening position and would never distract from actual listening, but it suggests the amplifier's or transmitter's overall quality.

For my first listening test, I popped in DTS's DVD-Audio disc of the Blue Man Group's The Complex. Nearly every track offers a full-out audio assault, and in addition to the aggressive surround mix, tons of percussive instruments are mixed into the discrete surround channels, giving them a real workout. The Kenwood accurately conveyed the swirling surround effects.

Next, I cued up DTS's Demo Disc #7 and enjoyed some movie clips. Again, the Kenwood system kept up - the sirens and screeching tires of the car chase from The Bourne Identity blared from all around me, perfectly following the action onscreen. It didn't take much listening, though, to confirm that the receiver's amplifiers far outperformed the Kenwood's. Sound was fuller and more detailed, making the Blue Man Group's instruments sound more "live." The differences were most noticeable in the low end, where the bass was tighter and punchier. But given that the receiver was set up to route deep bass to my subwoofer and that many movies use the surround channels mainly for ambient sounds like wind, rain, and crowd noise, the Kenwood's limitations didn't seriously detract from my enjoyment.

BOTTOM LINE If you can run wire from your receiver or amplifier to your surround speakers, do so. But in situations that don't demand the very highest performance, Kenwood's RFU-6100 system is an excellent solution to the hassle of getting wire to surround speakers. If you've been thinking about upgrading your 5.1-channel system by adding back surrounds but haven't found a practical way to run cable, this could be an easy and effective approach.