Transactions of the Society of Motion Picture Engineers · 1928 · 19 citations · 0 references
HumanitiesDiagnostic SciencesAcousticsEquipmentInstrumentationAcoustic MeasurementAudio RecordingRecording TechniquesRecording TechnologySound RecordingAudio Recording Technology
THE sound records I am about to describe are of the variable density type, and the method of making them is that developed by Bell Telephone Laboratories.