Amplifier projects

Very High Gain Audio Amplifier

This amplifier is designed to drive an 8 ohm speaker or phones to an extremely loud level at small input signal down to 700uV RMS. Although designed to be used with the parabolic microphone also listed on this site, this amplifier is also very well suited for use with any Crystal Set or other low signal output device. [more]

Posted in : Amplifier projects | Audio and Video


This is a simple do-it-yourself (DIY) headphone amplifier project that is fashioned primarily after the Class A MOSFET Headphone Driver project by Greg Szekeres and to some extent Mark’s DIY Class A 2SK1058 MOSFET Amplifier Project. The amplifier concept is simple and follows a typical single-ended class A circuit utilizing an active constant current source (CCS) in place of a passive resistor. A CCS doubles the efficiency of the circuit over that where a passive load resistor is used, bringing it to a maximum of 25%.[more]

Posted in : Amplifier projects

Ruby : A battery-powered amplifier

Ruby is a battery-powered amplifier.Ruby has many shades of sparkly clean all the way up to a great, natural overdrive. The input buffer helps to retain treble detail going into the LM386 chip. As you increase the Volume, you will start getting nice breakup. [more]

Posted in : Amplifier projects

Ibrahim’s CMoy Headphone Amplifiers

The amplifier is very popular among DIYers around the world.CMoy Amplifiers are named after Chu Moy, who designed the pocket battery-powered amplifier and published the paper on his website. These amplifiers were designed to give audio fidelity and power to headphones. A CMoy is powered from a single 9V battery and can last at least 40 hours of listening.This amp build around OPA134PA op-amp.[more]

Posted in : Amplifier projects

Ampwell House : Guitar Amp Attenuator

This is an 8 ohm attenuator built using an 8 ohm L-Pad. 4, 8 and 16 ohm versions are possible. The 4 ohm version would be built using a stereo 8 ohm L-Pad with the terminals wired in parallel. [more]

Posted in : Amplifier projects | Audio and Video