About: http://webisa.webdatacommons.org/451817984

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Adjacent to each disk was a coil, which picked up the varying magnetic field and whose output current was then summed with the others, via the keyboard???s key-switches, and amplified to produce the sound.
http://www.w3.org/ns/prov#wasQuotedFrom	designnews.com