We use a combination of both. We bring CD libraries to our events as well as computers. The computer is a great tool that allows us to bring our complete music library to handle unexpected and last minute requests or to quickly locate a song. All of our MP3’s are encoded from the original CD at a high bit rate to ensure a quality recording. You will not notice a difference between the two formats. The CD’s are there for reliability. If the computer were to crash we would have everything we would need on CD. All of your special dances will be played off of CD.