The typical FM transmitter either plugs directly into your MP3 player or acts as your player's stand while plugged into the car lighter jack. The former gives you freedom of movement, while the latter is a stationary option that often charges your MP3 player. Monster's innovative iCarPlay Wireless Plus is an $80 FM transmitter that attempts to offer the best of both worlds. It has an elongated cable-style design that has a lighter adapter on one end and a dock connection for an iPod on the other end of a 43-inch cord. About a foot away from the iPod is the controller unit, which features a legible red LED frequency display and six buttons.
Using the plus and minus buttons, you can hone in on any clear frequency except 87.7 and 87.9 (in odd-numbered tenths) and easily set up to three presets. The serpentine design allows passengers to operate the iPod, and it acts as an effective transmission antenna when stretched out, but it's easy to lose track of the iPod and the controller unit when you're driving; make sure you dedicate a place for the iPod. We always seemed to be fishing around for the controller or the iPod while driving, and it was usually in the passenger seat or on the floor. The nondistinctive buttons also make blind control a challenge. And for backseat DJs, the cable is just too short to operate while sitting in the back. One observation: It's interesting that most users have the impression that the iPod is connected directly to the stereo, rather than transmitting wirelessly.
On the positive side, the transmission signal is robust, and sound quality is decent for an FM transmitter, with distinguishable highs and lows. However, for the best sound, you'll need to play with the position of the iPod/iCarPlay combo. Of course, you'll fare much better in nonmetro areas.
Overall, the pricey Monster iCarPlay Wireless Plus is a decent performer, but it can be cumbersome while driving as it is basically a three-and-a-half-foot cable. Though we love the fact that it recharges the iPod, we don't like that it's one-dimensional with no line input.