The transmitter includes a special cable that plugs into your AV receiver or amplifier--it's labeled clearly and should connect to any spring-clip or binding post found on the back panel of any stereo or surround system. The transmitter can also directly accept a stereo 3.5mm plug, which we alternatively used to hook up an iPod. We used the iPod volume control to adjust the volume of the sound of the speakers being fed by the KEF Wireless System.
A third hookup possibility involves using the KEF Universal Wireless System to power speakers in another room of your house or apartment--perfect for utilizing a "zone 2" feature of your AV receiver without stringing wires through the wall. KEF doesn't specify a maximum range for transmission, but it worked perfectly well in a room we tried that was about 25 feet from the transmitter.
As far as competition is concerned, aside from the aforementioned RocketFish Wireless Kit--which is far cheaper--anyone looking for just a pair of stereo speakers should consider the JBL OnAir Control 2.4G, which retails for $350. Furthermore, anyone considering KEF's excellent KHT 5005.2 speaker system will want to investigate the matching KHT 5005.2W Wireless Kit. It's essentially a version of the Universal Wireless System that's made to exactly match the rear speakers of the KHT 5005.2 system. The receivers attach directly to the rear speakers and are integrated right into the stands--only the AC power cord for each rear speaker is necessary.
Once we had the KEF system up and running, everything worked perfectly right off the bat--no need for the sort of time-consuming setup process that we're used to with a Wi-Fi network. We noted the system was quiet--there was absolutely no hiss or whistling tones emitted by the speakers. Only occasional pops were noticeable, but they were barely audible. We were intently listening for digital artifacts, and the pops didn't interfere with our enjoyment of music or home theater.
Sound quality claims are easy to make, but every other wireless system we've tested to date has been permanently mated to HTIB speakers, so we could never verify the claims. The KEF Universal Wireless System is the first we've tried that can be used with any speaker. True, its prime mission is to serve as a wireless connection for surround speakers in home theater systems, but we decided to first test the KEF Wireless system with high quality Dynaudio Contour 1.1 speakers, as "front" speakers in stereo. The sound was excellent, with good, solid bass, natural midrange, and clear treble. There were only the most minimal of processing artifacts (the very mild popping sounds we mentioned earlier), and most of the time, we never heard any pops. Stereo separation was first-rate.
We next used the KEF system with the Dynaudio speakers as surround speakers in our all-Dynaudio system. The wireless sound was so good, we quickly forgot the surround speakers weren't hooked up with wires (and used that way, we never heard the popping sounds). Yes, KEF is charging a high premium for its wireless kit, but that's because it delivers the goods. If you're looking for no-compromise wireless, the KEF Wireless System is highly recommended.