Mp3 Player Turntable Drive
This is the setup I chose to use for my DIY turntable. Its simple, adjustable, and should give high performance. It was initially inspired by the infamous Altmann Turntable and by the writings of diyaudio.com user Mark Kelly.
You can use two kinds of motor, with a small 12v motor, a stepper or AC synchronous you can hook the motor right up to a small amplifier. I use a Lepai. In my case the motors are 240v motors. To increase the voltage from the amplifier, I use a step down transformer wired backwards.
The diagram shows a single channel/phase. The motors are 2 phase and need two transformers and channels per motor. With the 240v motor the 110v inputs are wired in series to give the 240v output, the 9v outputs are wired in parallel.
Creating the 60hz wav file for the Mp3 player is Fairly simple. I used Audacity .
In Audacity generate the sine wave, then duplicate, then use the time tool to move one wave 90 degrees out of phase from the first.
Then simply export as a stereo .wav file for playback on the device of your choice.
An easier way to do it is with a recent ipod or iphone with access to the app store. Sig Gen will generate the 2 signals and allows you to customise both frequency and phase shift on the fly.