The main concept behind our clocks is a memory card music module. This card will hold many music files. It ships with over 50 music files in various folders. This allows many songs to play before hearing the same songs all over again. We use an oval speaker mounted in a sealed enclosure on bottom of clock. This produces a better sounding speaker system with clarity and body.  Buttons are used for play, volume and various other functions. We have eliminated the problem of knob volume controls that tend to become erratic or fail to work altogether. Songs can play every hour or every 1/4 hour. There is even a mode that will play chimes like a Shelf clock, Grandfather clock, Cuckoo clock, Train sounds and Nature Sounds.