In this post I have explained about a simple Hi-Fi balanced microphone preamplifier circuit and also evaluate the calculations, specifications of the design through formulas. What is a Balanced Preamplifier A “balanced” amplifier or differential amplifier possesses not one but two distinct inputs and only the difference amongst these inputs is actually amplified. To elucidate […]
Newly Updated Circuit Projects:
Simple 10 Watt Amplifier Circuits using Transistors
In this post I will comprehensively explain 3 easy to build 10 watt power amplifier circuits, which can be built using discrete parts, such as resistors, transistors, and MOSFETs. The MOSFETs used in these designs are the ordinary IRF540 and IRF9540, that are easily avail;able in the market and are quite inexpensive. True Complementary 10 […]
Op Amp Preamplifier Circuits – For MICs, Guitars, Pick-ups, Buffers
In this post I have explained a variety of op amp preamplifier circuits, and there should be an appropriate layout here for almost any standard audio preamplifier application. As the name suggests itself, a preamplifier is an audio circuit which is used before a power amplifier, or between a small signal source and a power […]
Simple Mini Audio Amplifier Circuits
In this article we are discussing a handful of simple, mini audio amplifier circuits which can be built quickly for amplifying very tiny input signals into audible speaker outputs. 1) 1 Watt Amplifier Circuit The first simple mini audio amplifier circuit works with a ‘complementary’ output stage, having a single NPN and a single PNP […]
0 to 50V, 0 to 10amp Variable Dual Power Supply Circuit
In this post I have explained a simple yet very useful 0 to 50V dual power supply circuit which will enable a full 0 to maximum dual voltage +/- control of the input power supply DC. It also includes a wide range current control feature right from 0 to 10 amps. The idea was requested […]
GSR Sensor Circuit for Biofeedback Measurements
In this post I have explained how to build a very simple GSR sensor circuit using just a couple of transistors and a few other passive components. A GSR (Galvanic Skin Resistance) sensor, also known as a skin conductance or electrodermal activity sensor, measures the electrical conductance of the skin, which changes in response to […]





