The multi-channel music sequencers allows you to program in beats to a song using different variations of noteblocks. This is a similar approach to the programmable piano, except that it allows the player to program different channels with different instruments. Each channel can even be played at a different tempo and timing.
If you like redstone and music or want to see to build a music sequencer just like FVDisco's join us this Saturday, December 31st at 4pm CST!
Follow us on Twitter @MinecraftHowTo!