Hi Stephen The WAV files need to be placed in the "Audio" folder on your USB. They also need to be named "TAKExx.wav" with xx being numbers from 01 up to 99 You may find the audio files you've created will need to be dropped in volume by about 20-30% for them to be at a reasonable volume to play over the top of when playing back through the AP-650. Unfortunately on this model you can't control the volume of the audio file playback on the piano, so you'll need to have this set before hand. To play the Wave file: 1) Have USB plugged in 2) Press the AUDIO RECORDER button as many times as needed until the light is solid (not flashing) 3) While holding the FUNCTION button, press the AUDIO RECORDER button 4) Use the Up/Down arrow buttons to choose which file you wish to play - the numbers here correspond to the last two digits of the file name (TAKExx) 5) Press Play - away she goes!
Jared Beaney's post in How Do I play Back a WAV Audio File from USB Stick on AP-650? was marked as the answer