A karaoke system sounds a karaoke song designated according to a request command. The system includes a record unit defining a closed data source for readably recording a karaoke song, and a playback unit for reading the record unit to reproduce an audio signal representative of the karaoke song such...http://www.google.com/patents/US5654516?utm_source=gb-gplus-sharePatent US5654516 - Karaoke system having a playback source with pre-stored data and a music synthesizing source with rewriteable data
