LOS ANGELES, CA  [Wednesday Sep.20.2006]  /Mix103FM.com/ -- When Justin Timberlake wants to know whether or not a song is a sure-fire hit, he takes it on the road, and I don't mean on tour.

According to TeenMusic.com, the sensual R&B singer plays a preliminary version of a tune full-blast in his car. He said, "I always do the car test. You put the songs on a CD in their rough form, you turn it up and you drive around playing it. We did it in Miami, Virginia, LA and Tennessee."

So the next time you hear a car stereo blasting some fresh beats, who knows, it may be JT.

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