In this post I have explained the construction of a ultrasonic directive speaker system also called parametric speaker which may be used to transmit an audio frequency over a targeted spot or zone such that the person situated exactly at that spot is able to hear the sound while the person next to him or […]
Audio and Amplifier Projects
Make a Simple Class D Amplifier Circuit
In this article I have explained two simple class-D amplifier projects which can be built at home with extremely high efficiency results. A Class D amplifier is also known as switching amplifier. This technology uses pulse width modulation or PWM for digitally amplifying small analogue music signals into high power, high efficiency audio signals. Why […]
Simple FM Radio Circuit Using a Single Transistor
When it comes to making an FM receiver it’s always thought to be a complex design, however the one transistor simple FM receiver circuit explained here simply shows that it isn’t the case after all. Here a single transistor acts as a receiver, demodulator, amplifier to constitute a wonderful tiny FM radio. It’s basically based […]
Sound Activated Automatic Amplifier Mute Circuit
The following article presents a simple sound operated/activated amplifier muting circuit which enables the amplifier to silence itself as soon a voice or an external sound occurs across the detector MIC. The circuit was requested by Mr. Seok Sothea. Technical Specifications I want to make a circuit about voice interrupt music..this circuit consists of two input, audio […]
10 Band Graphic Equalizer Circuit Diagram
The proposed 10 band graphic equalizer circuit can be used in conjunction with any existing audio amplifier system to get an enhanced 10 stage audio processing, and customized tone control. The circuit can be easily converted to a 5 band graphic equalizer by simply eliminating 5 stages from the shown design The Circuit Concept A […]
Low Pass Filter Circuit for Subwoofer
In this post I have explained a simple low pass filter circuit which can be used in conjunction with subwoofer amplifiers for acquiring extreme cuts or bass in the frequency range 30 and 200Hz, which is adjustable. How it Works Several low pass filter circuits for subwoofer application are presented all over the net however […]





