Q. I saw your recent column on digitizing music from a turntable with a built-in USB output. I have an old Sansui turntable with red-white analog outputs. What do I need to digitize my hundreds of albums? —L.J., Minneapolis A. You need a phono preamp with a USB output. Connect the ground wire and red-white cables from the turntable to the corresponding connections on the preamp, and then connect the USB output to your computer. The preamp has analog outputs that connect to your receiver/amplifier or powered speakers for monitoring playback when recording. You cannot connect these outputs to th…