The RX-V475 receiver does not come with a phonograph/turntable pre-amp and to use a phonograph/turntable with it, you will need a phonograph/turntable pre amp to amplify the signal. Phonograph/turntable line levels typically range from 2-5mV. The line level inputs on the receiver want to see at least 150mV. So it will need the pre-amp to amplify the signal.
For information on purchasing a turntable pre amp, consult a local Yamaha dealer or local electronics shop. Yamaha does not manufacture a turntable pre amp.