This audio amplifier project is a class AB audio power amplifier using a TDA2003 module power amplifier. It is easy to construct and has only a few external components. The module is designed with short circuit and thermal protection. It can drive loads as low as 1.6 ohm and is capable of delivering over 10 watts from a 16 V DC power supply. Figure 1 shows the TDA 2003 packaged and pin configuration.
Simple To Build 10 W Audio Amplifier! – [Link]
It is a 2x56W stereo amp based on National Semiconductor’s LM3876T chip (they come in 2 versions T and TF the latter having an insulated case), this type of amp is also known as a gainclone because it is an improved copy of Gaincard amplifier. seriously this amp can outperform most commercial amplifiers/receivers (minus the video upscaling/switching) when built properly ie it has very low THD you will not be disappointed by how good it sounds.
56W LM3886 / LM3876 Gainclone - [Link]
Many electronic projects require the use of a small audio amplifier. Be it a radio transceiver, a digital voice recorder, or an intercom, they all call for an audio amp that is small, cheap, and has enough power to provide adequate loudness to fill a room, without pretending to serve a disco! About one Watt RMS seems to be a convenient size, and this is also about the highest power that a simple amplifier fed from 12V can put into an 8 Ohm speaker.
LM386 Amplifiers – [Link]
The following is a 70W amplifier based on a popular TDA7294 chip. Main technical characteristics of the amplifier are as follows: input resistance – 22 kOhm input voltage – 750 mV nominal output power at 4 ohms and THD 0.5% – 70 Watts Frequency Range – 20 … 20000 Hz supply voltage – ± 27 V, quiescent current – 60 mA. The amplifier has a built-in thermal protection, and protection against overload and short circuit in the load.
70W TDA7294 Amplifier – [Link]
This project is a headphone amplifier based on BUF634 and OPA627. The amplifier operates in class-A.
BUF634 / OPA627 headphone amplifier - [Link]
This project is a Class-A Audio Amplifier based on 2SA1943 and 2SC5200 complimentary transistor pairs. This Super Class-A Amplifier is fully running at a bias of about 1.65A @ 35V, which it resulting in about 58W of continuous dissipation per transistor in the output stage. In this condition, you can highly imagine that the heat sink runs in a hotter temperature, where it can reach approximately 40 Celsius degrees!
Super Class-A Amplifier – [Link]
This project is a homemade speaker. RobertG writes:
It’s a simple speaker, that may be build at home from inexpensive and freely available materials: magnet, cardboard and tape, isolated wire from signal transformer and mini-jack cable from broken headphones.
Homemade speaker - [Link]
DS1802 is a Stereo Digital Volume Control IC. It consists of two 65-position, 45kΩ digital potentiometers with logarithmic resistance properties incrementing 1dB per step. It can be operated under automatic software control via a serial 3-wire interface where wiper settings are written with 8-bit words, or under push button control with simple contact closure.
DS1802 Stereo Digital Volume Control – [Link]
This project is an easy audio amplifier based on 8 pin DIP LM386 integrated circuit.
The potentiometer is the volume control. The heatsink is screwed to an LM7812 12V voltage regulator. There are a couple of caps and a diode on there. The wire with what looks like gum on the end of it is actually the headphones jack wire with a three-pin header molded onto the end using that really cool putty “as seen on TV” that you knead together and it forms really hard parts. I used it to protect the super-thin wires of the headphones jack. The little chip on that board is the LM386. The red- and black-tipped wires coming into the top of the breadboard just left of the diode and the voltage regulator are the leads from a Radio Shack 12V, 500 mA wall wart.
LM386 Easy Amp – [Link]