GB1479005A - Musical signal systems - Google Patents

Abstract

1479005 Electronic musical instruments; teaching devices MATSUSHITA ELECTRIC INDUSTRIAL CO Ltd 24 June 1974 [23 June 1973] 28001/74 Headings G5J and G5X A musical signal system comprises a tone generator 26 actuated by a signal Sm from a memory device 24 such that any electrical audio frequency input signal S100 sensed by a sensor 22 as falling within predetermined frequency bands, each containing a note of a musical scale, is output as a more accurate representation of that note. The signal S100 may be derived from a human voice or musical instrument. The input bands may be abutting, separated or overlapping (e.g. Figs. 2, 12 and 13, respectively, not shown) and the outputs may be scale notes in the same input frequency bands or shifted therefrom by a predetermined multiple (Figs. 2 and 14 respectively, not shown) or may be a frequency lying in an output band which is narrower than the input band (Figs. 17, 19, not shown). When the input frequency bands overlap, two output frequencies may result and when the input bands are separated by a gap, no tone may be output if an input frequency is in the gap. The output may be controlled to provide vibrato or portamento as sensed at the input (Figs. 21, 22 respectively, not shown) or may be changed from one musical scale to another based on a different standard concept pitch (Fig. 20, not shown). The tone generator 26 may be suitably controlled separate oscillators (e.g. Figs. 3 and 5, not shown) or may be a controlled frequency divider coupled to a single oscillator (Figs. 9 and 10, not shown). The system may be used for teaching pitch accuracy.