US 4,050,343 A · Electronic music synthesizer

Abstract

An electronic music synthesizer is disclosed in which the sound producing chain includes a voltage-controlled oscillator, band-pass filter, low-pass filter, and amplifier in which selected control currents are supplied to low impedance points within the synthesizer circuit from a resistor matrix. The synthesizer produces sounds approximating different acoustic musical instruments or having different tonal qualities by the application of a predetermined voltage to one of fifteen input columns of the resistor matrix with selected other columns being grounded. The currents provided by the resistor matrix in combination with other externally generated currents control the center frequency and bandwidth of the band-pass filter, the cutoff frequency of the low-pass filter, the gain of the voltage-controlled amplifier, the time constants of transient contour currents used to control the filters and amplifier, and the waveform produced by the voltage-controlled oscillator. Specialized keyboard, waveshaping, contour generating and modulating circuits are also provided.

Claims12

Dependent claims

An electronic music synthesizer, comprising:

a sound producing chain having a plurality of voltage-controlled elements;
a low impedance control input for each of said elements;
means coupled between each control input and its respective element for developing a control voltage proportional to the sum of the control currents supplies to the respective input;
means including a resistor matrix coupled to said control inputs for supplying predetermined control currents to said inputs to control the functions of said elements, wherein said matrix comprises a set of rows and a set of columns, means for coupling one of said sets to a source of constant voltage, and means coupling the other of said sets to said control inputs;
and
means coupled to said inputs for supplying pitch-related control currents to said control inputs in parallel with said resistor matrix.

3 more elements

In an electronic music synthesizer means for generating audio signals corresponding to predetermined musical sounds;

a voltage-controlled oscillator for generating an output signal having a frequency proportional to an applied pitch control voltage;
means coupled to said oscillator for applying a pitch control voltage to it;
voltage controlled elements including a voltage controlled band pass filter adjustable in both center frequency and band width by the application of control voltages, a voltage controlled low pass filter having a low pass cut-off frequency adjustable by the application of a control voltage, and a voltage controlled amplifier having a gain adjustable by the application of a control voltage;
means for connecting said voltage controlled elements in series and for applying an oscillator output signal to said band pass filter, an audio output terminal coupled to said series connected voltage controlled elements;
and a master control circuit for generating a number of control voltages applied selectively to said band pass filter, to said low pass filter and to said voltage controlled amplifier for controlling respectively the band width and center frequency of said band pass filter, the low pass cut-off frequency of said low pass filter and the gain of said voltage controlled amplifier, said master control circuit including a resistor matrix having a predetermined number of input columns and a predetermined number of output rows, means for applying a predetermined voltage to an input column and for grounding selected other input columns, resistive elements of preselected values between selected input columns and rows, said rows being connected to low impedance current summing points within said master control circuit, said master control circuit including means for generating said control voltages in response to the currents supplied to said summing points from said resistor matrix.

2 more elements

Dependencies are inferred from the claim text.

Electronic music synthesizer

Life of this patent

Electronic music synthesizer

Life of this patent

Abstract

Claims12