60-dB Range Compressor For Audio

A compressor circuit shown in the schematic diagram below can produce consistent output of 1.4V P-P over entire 60dB range that is very useful for audio level/volume stabilization.  As the main components, this circuit uses a 741 opamp and JFET. With input range of 20mV to 2oV, this circuit has delay time of 0.4s (decay time)  and response time of […]

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Compressor Circuit with 570/571 Compandor IC

Compressor circuit provide high gain for low amplitude input and provide low gain for high amplitude input. This action, in effect, produce a nearly constant amplitude even though the input has very high dynamic range (very high amplitude variation from time to time). The action of compression like this is needed in some situation, such as in maximizing modulation depth […]

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AGC (Compressor) Speech Processor

This is a speech processor circuit that can be used in communication radio circuit. This circuit consist of two sections, they are amplification and compression or dipping. The combination of these processing will improve the  SSB communication intelligibility and provide higher average level while avoiding clipping. The 100K pot is used to adjust the compression degree, as well as adjusting […]

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Mic/Guitar Compressor with Transitor Bias Control

This is a compressor circuit that can be used for dynamic mic, condenser mic, or electric guitar pickup. This circuit doesn’t produce very good sound output, but it has very stable amplitude/volume. This compressor circuit design is unique since it uses base current control for manipulating the gain. Here is the schematic diagram of the circuit: The first and second […]

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TL084 Audio Compressor (AGC)

Compressor or AGC (automatic gain control) is used to manipulate the average amplitide of audio signal, to produce relatively constant volume of signal from high dynamic signal source. The 2N3819 JFET (which is used as a voltage controlled resistor) is the key component. Control voltage which is derived by full-wave rectification followed by a peak detector is provided by the […]

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Audio Speech Compressor

There are many low power SSB rigs and kits don’t have any real speech processor circuitry, although there is a built in speech processor in most modern HF. Speech processing is an important thing, when the SSB is operated at low power to get through the QRM. Speech processing can be done by this circuit. This is a simple and […]

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Dynamic Compressor, Self Powered Circuit Design

This dynamic compressor will give about 20dB compression, at very wide input signal range 100 mV to 10 V.  Another advantage of this circuit is that this circuit doesn’t need any power supply, we call it self powered, or more accurately, signal-powered compressor. Here is the schematic diagram of the circuit: A part of the signal is rectified by D1 […]

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