Multi-channel control circuit with D-C operated control devices

Claim 2

A control circuit arrangement for effecting a plurality of predetermined control functions in a multi-channel system, comprising in combination: means for providing at least one signal path including a signal current steering device having first and second outputs for supplying varying relative amounts of an input signal to such outputs in response to a variable control signal; an output terminal; means for receiving and amplifying a desired signal and selectively applying the same to said signal path and to said output terminal; means for supplying a variable control signal to said current steering device; means coupling the first output of said steering device with said output terminal for feeding forward signals from said steering device for a boosting action; and means coupling the second output of said steering device with said receiving and amplifying means in a feedback circuit for attenuating signals applied from said receiving and amplifying means to said output terminal.

Claim 3

A control circuit arrangement in accordance with claim 1, wherein the same is disposed in a single integrated circuit.

Claim 4

A control circuit arrangement in accordance with claim 1 wherein said signal current steering device is in the form of a differential amplifier having a signal input to which the signal from said receiving and amplifying means is applied and having first and second respective current signal paths therethrough coupled with said first and second outputs thereof, respectively, the selection of which is determined by said variable control signal.

Claim 5

A control circuit arrangement in accordance with claim 3 wherein said differential amplifier includes first, second and third transistor devices, each with base, emitter and collector electrodes, said emitter electrodes of said first and second transistors being connected together and to the collector electrode of said third transistor, said base of said third transistor serving as the input for said applied signal, and the collector electrodes of said first and second transistors serving as said first and second outputs, said variable control signal being coupled to one of said base electrodes of said first and second transistors for varying the relative conductivities thereof.

Claim 6

A control circuit arrangement in accordance with claim 3 wherein said signal receiving and amplifying means includes a differential amplifier having one output coupled with said output terminal; another output coupled with said signal current steering device to supply input signals thereto, a first input coupled to receive said desired signal and a second input coupled with the second output of said steering device.

Claim 7

A control circuit arrangement in accordance with claim 4 further including a d-c balancing complementary differential amplifier interconnected in parallel with said first named differential amplifier.

Claim 8

An audio control circuit arrangement for effecting a plurality of audio control functions in a multi-channel system comprising in combination: means providing a plurality of signal paths, each of which includes at least one signal current steering device having first and second outputs for supplying varying relative amounts of an input signal to such outputs in response to a variable control signal; an output terminal; means for receiving and amplifying a desired signal and selectively applying the same to each of said signal paths and to said output terminal; filter means interposed between said receiving and amplifying means and the input to said signal current steering device in at least one of said signal paths to restrict the frequency range in said signal path; means for supplying variable control signals to said current steering devices; means coupling the first output of each of said steering devices with said output terminal for feeding forward signals from said steering devices for a boosting action: and means coupling the second output of each of said steering devices with said receiving and amplifying means in a feedback circuit for attenuating signals applied from said receiving and amplifying means to said output terminal.

Claim 9

An audio control circuit arrangement for effecting a plurality of audio control functions in a multi-channel system comprising in combination: means providing a plurality of signal paths, each of which includes at least one signal current steering device having first and second outputs for supplying varying relative amounts of an input signal to such outputs in response to a variable control signal; an output terminal; means for receiving and amplifying a desired signal and selectively applying the same to each of said signal paths and to said output terminal; filter means interposed between said receiving and amplifying means and the input to said signal current steering device in at least one of said signal paths to restrict the frequency range in said signal path; means for supplying variable control signals to said current steering devices; means coupling the first output of each of said steering devices with said output terminal for feeding forward signals from said steering devices for a boosting action: and means coupling the second output of each of said steering devices with said receiving and amplifying means in a feedback circuit for attenuating signals applied from said receiving and amplifying means to said output terminal.

Claim 10

A audio control circuit arrangement in accordance with claim 7 wherein the same is disposed in a single integrated circuit.

Claim 11

An audio control circuit arrangement in accordance with claim 7 wherein said signal current steering devices are each in the form of a differential amplifier having a signal input to which the signal from said receiving and amplifying means is applied and having first and second respective current signal paths therethrough coupled with said first and second outputs thereof, respectively, the selection of which is determined by said variable control signal.

Claim 12

An audio control circuit arrangement in accordance with claim 9 wherein each of said differential amplifiers includes first, second and third transistor devices, each with base, emitter and collector electrodes, said emitter electrodes of said first and second transistors being connected together and to the collector electrode of said third transistor, said base of said third transistor serving as the input for said applied signal, and the collector electrodes of said first and second transistors serving as said first and second outputs, respectively, of each of said steering devices, said variable control signal being coupled to one of said base electrodes of said first and second transistors for varying the relative conductivities thereof.

Claim 13

An audio control circuit arrangement in accordance with claim 9 wherein said signaL receiving and amplifying means includes a differential amplifier having one output coupled with said output terminal; another output coupled with said signal current steering devices to supply input signals thereto, a first input coupled to receive said desired signal and a second input coupled with the second outputs of said steering devices.

Claim 14

An audio control circuit arrangement in accordance with claim 10 further including a d-c balancing differential amplifier interconnected in parallel with each of said first named differential amplifiers.

Claim 15

An audio control circuit arrangement in accordance with claim 7 wherein respective signal paths are provided within which bass, treble, balance and volume control functions may be effected.

Claim 16

An audido control circuit arrangement in accordance with claim 7 wherein said filter means includes a high pass filter in one of said signal paths for restricting the same to treble frequencies and a low pass filter in another of said signal paths for restricting the same to bass frequencies.

Claim 17

An audio tone control arrangement for effecting treble and bass tone control functions in an electronic apparatus, comprising in combination: a first signal path including at least one signal current steering device and a high pass filter; a second signal path including at least one signal current steering device and a low pass filter; a reference output terminal; means for receiving and amplifying a desired signal and applying the same to said reference output terminal and to each of said first and second signal paths; a source of potential; and variable resistance means interconnected between said potential source and a respective one of said signal current steering devices whereby the applied signal to each of said signal paths may be selectively fed forward to said reference output terminal for a boost action or fed back to said receiving and amplifying means for a relative attenuation.

Claim 18

An audio tone control arrangement for effecting treble and bass tone control functions in an electronic apparatus, comprising in combination: a first signal path including at least one signal current steering device and a high pass filter; a second signal path including at least one signal current steering device and a low pass filter; a reference output terminal; means for receiving and amplifying a desired signal and applying the same to said reference output terminal and to each of said first and second signal paths; a source of potential; and variable resistance means interconnected between said potential source and a respective one of said signal current steering devices whereby the applied signal to each of said signal paths may be selectively fed forward to said reference output terminal for a boost action or fed back to said receiving and amplifying means for a relative attenuation.

Claim 19

An audio tone control circuit arrangement in accordance with claim 15 wherein the same is disposed in a single integrated circuit with said variable resistance means being provided external thereto for manual adjustment accessibility.

Claim 20

An audio tone control circuit arrangement in accordance with claim 15 wherein said signal current steering devices are in the form of differential amplifier arrangement having respective current signal paths therethru, the selection of which is determined by setting of said variable resistance means.

Claim 21

An audio tone control circuit arrangement in accordance with claim 17 wherein each differential amplifier includes first, second and third transistor devices with base, emitter and collector electrodes, said emitter electrodes of said first and second transistors being connected together and to the collector electrode of said third transistor, said base of said third transistor serving as the input for said applied signal, and the collector electrodes of said first and second transistors serving as respective outputs, said variable resistance elements being coupled to one of said base electrodes of said first and second transistors.

Claim 22

An audio tone control circuit arrangement in accordance with claim 18 wherein additional means in the form of complementary current steering devices are included to maintain balance in the d-c levels at the outputs of said differential amplifier.

Claim 23

An audio tone control circuit arrangement in accordance with claim 19 wherein said d-c balancing complementary current steering devices include an additional differential amplifier arrangement interconnected in parallel with said first named differential amplifier.

Claim 24

An audio tone control arrangement in accordance with claim 15 wherein said signal receiving means includes a differential amplifier with one output connected to said reference output terminal and a second output connected to said filter means in said signal paths.