Prerecording of the accompaniment to a singer who then listens through headphones to a replay as he /she performs. The two signals are mixed to give the final recording.
"For music lovers with rare LPs that didn't make it to CD, your service is invaluable. Your sound restoration makes the quality of the CD better than the vinyl itself, with all the hisses and pops eliminated, and reproducing the album cover is a great touch. You guys are my first and only choice for any transfers I'll need in the future."