The Synthetic Production and Control of Acoustic Phenomena by a Magnetic Recording System

In recent years there has been an increasingly active search for an electroacoustic system for producing and controlling reverberation and associated phenomena. This paper describes an electromagnetic method of producing and controlling reverberation by the use of a magnetic tape recording system. It consists of recording a sound pattern magnetically on steel tape. The signal is picked up from the tape at frequent split-second intervals and reproduced at any desired level or characteristic. The tape is arranged for driving in an endless helical loop. An obliterating head which continuously obliterates the record is placed just before the first recording head. The phenomena of reverberations and the various methods which have been suggested by others for controlling reverberation synthetically, such as the electrooptical, electromechanical, mechanical-recording, and the reverberation-chamber methods, are briefly discussed. The paper also outlines other uses for the magnetic tape system in the study of acoustic phenomena both synthetically and analytically.