Amplifier and Audio Circuits


7 Watt Audio Power Amplifier

Small but powerful multipurpose amplifier This small amplifier is constructed around the TDA2003 IC, capable of delivering 4Wrms at 4ohms. The TDA 2003 has improved performance with the same pin configuration as the TDA 2002. The additional features of TDA 2002, very low number of external components, ease of assembly, space and cost saving, are […]


4 Transistor Amplifier for Small Speakers

The circuit below shows a 4-transistor utility amplifier suitable for a variety of projects including receivers, intercoms, microphones, telephone pick-up coils, and general audio monitoring. The amplifier has a power isolation circuit and bandwidth limiting to reduce oscillations and “motorboating”. The values are not particularly critical and modest deviations from the indicated values will not […]


2 Channel Audio Mixer using Transistors

This 2 channels audio mixer is based on the 2n3904 transistors which forms 2 pre-amplifiers. The first preamplifier of the audio mixer has a high gain and can be used for microphone input, and the second one can be used to control the input of the audio level. This two channel audio mixer require a […]


Dual Polarity Unregulated PSU For High-End Audio Amps

A power supply suitable for use with the hi-fi amplifiers presented in the predeeding project is perfectly simple, and no great skill is required to build (or design) one. There are a few things one should be careful with, such as the routing of high current leads, but these are easily accomplished. Design of this […]


Amplifiers and Loudspeakers Protector with IC LM393

The short circuit proof outputs of amplifiers and speakers, throw some interesting elements, such as the isolation of the speakers from the exit of the amplifier, when is a constant tension presented abandoned or if the heat sink temperature rises excessively, the simultaneous and delayed connecting speakers to the amplifier so until we stop them, […]


10 to 14W Class A Audio Amplifier

I have built this amplifier and it does sound good. It requires a preamp as it hasn’t got much gain. It requires big heat sinks and a large transformer and a great power supply and careful wiring, but in the end it is extremely simple and it sounds very good. The zener diode rejects any […]


Boomer Audio Power Amplifier Using LM4906

The well-known LM386 is an excellent choice for many designs requiring a small audio power amplifier (1-watt) in a single chip. However, the LM386 requires quite a few external parts including some electrolytic capacitors, which unfortunately add volume and cost to the circuit. National Semiconductor recently introduced its Boomer® audio integrated circuits which were designed […]


Super Simple 3 Watt Audio Power Amplifier

Here is the circuit diagram of superb mini audio power amplifier, That can be power with 4.5 volt dc to 18 volts dc (maximum). This amplifier is based on TDA1015, Product of NXP Semiconductors formerly PHILIPS Semiconductors. The TDA1015 is a monolithic integrated audio amplifier circuit in a 9-lead single in-line (SIL) plastic package. The […]


Hybrid Headphone Amplifier Circuit

Potentially, headphone listening can be technically superior since room reflections are eliminated and the intimate contact between transducer and ear mean that only tiny amounts of power are required. The small power requirement means that transducers can be operated at a small fraction of their full excursion capabilities thus reducing THD and other non-linear distortions. […]


20 Watt Power Amplifier

This IC chip was designed specifically for use in power boosting applications in automobiles. It is self protecting against short circuits and thermal problems. In the bridge configuration shown it will deliver 20 watts of power into a 2 ohm speaker operating at 14.4 volts.