How to Buy an AM-FM Radio Tuner
Typically, a radio tuner offering local AM-FM radio stations is built into your A/V (audio/video) receiver. You'll need a stand-alone radio tuner for your home theater system, however, if you're using separate components rather than an all-in-one A/V receiver.
Separate components break down the functions of the receiver into these parts: a radio tuner, a power amplifier (or power amplifiers), and an A/V controller. In general, using separate components offers more flexibility and better overall performance than an all-in-one A/V receiver.
If you do buy separate components instead of an A/V receiver, you'll probably have to buy a radio tuner and plug it in to your system as an audio source device, just as you plug a CD or DVD-audio player in to your system. AM/FM radio tuners usually cost about $150 to $500 (though, like any A/V component, you can buy high-end versions that cost ten times the average).
Things to look for include the following:
AM and FM sensitivity: Measured in the oh-so-familiar decibel femtowatt (dBf), this is a measurement of how well the tuner can pick up signals. The lower this number (it’s usually in the range of 9 to 11 dBf), the better.
Adjustable selectivity: Some tuners come with a switch on the front (or on the remote control) that lets you choose between wide and narrow selectivity. The wide mode gives you better reception and sound quality on powerful stations, whereas the narrow mode can tune in weak signals from distant stations while avoiding interference from stations on adjacent frequencies.
Antenna diversity: Not a necessity, but some fancier tuners have two antenna inputs. You can manually or automatically have the tuner choose between the inputs when you’re trying to pull in a radio station.
If you’re lucky enough to live in an area with some good radio stations, you might want to invest in a high-quality tuner near the top of your price range.