Introduction: Audio Amplifier Circuit Using Mosfet Transistor

Picture of Audio Amplifier Circuit Using Mosfet Transistor

How to make an audio amplifier using just one mosfet transistor

An audio power amplifier (or power amp) is an electronic amplifier that strengthens low-power, inaudible electronic audio signals such as the signal from radio receiver or electric guitar pickup to a level that is strong enough for driving (or powering) loudspeakers or headphones. This includes both amplifiers used in home audio systems and musical instrument amplifiers like guitar amplifiers.There are lots of circuit diagrams out there but we have selected the easiest one that has a mosfet transistor.

Step 1: Simple Power Amplifier Circuit

Picture of Simple Power Amplifier Circuit

Simple power amplifier circuit components

Power amplifiers make the signal—whether it is recorded music, a live speech, live singing, an electric guitar or the mixed audio of an entire band through a sound reinforcement system—audible to listeners. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers and speaker enclosures.

Poweramp components :

Mosfet transistor IRFZ44N

Resistor 10K

Capacitor 440v 30mF(not crucial)

Speaker+Jack cable+power supply(5v-9v)

Step 2: Jack Audio in Cable Connection

Picture of Jack Audio in Cable Connection

In order to make the audio input for our audio amplifier we have to make the connection from the audio into our amplifier, for this, we will need a jack mono/stereo cable.How to find the correct cable connection is very simple

this type of cables from bottom to top have layers divided by some small black strips.Now on the bottom part and also the bigger part is the ground or negative terminal, and the rest is positive or signal left and right if is a stereo cable.For this you will use the multimeter in the continuity selection and from each metal connection of the jack audio cable to the opened wires wi will find which one is which.

Step 3: Audio Amplifier Circuit Using Mosfet Transistor

Picture of Audio Amplifier Circuit Using Mosfet Transistor

You have the circuit diagram of a simple audio amplifier using a mosfet transistor and the representation of each electronic components and the connection between audio in and speaker audio out.

While power amplifiers are available in standalone units, typically aimed at the hi-fi audiophile market (a niche market) of audio enthusiasts and sound reinforcement system professionals, most consumer electronics sound products, such as clock radios, boom boxes and televisions have relatively small power amplifiers that are integrated inside the chassis of the main product.

Step 4: Audio Amplifier Sound Test

Picture of Audio Amplifier Sound Test

Let's make a sound test in the video linked you will find the sound test of our homemade audio amplifier with simple electronic components, now this is not going to replace your home system or subwoofer this is just the practical application and demonstration of an audio amplifier in its primitive form.

The audio amplifier was invented in 1909 by Lee De Forest when he invented the triode vacuum tube (or "valve" in British English). The triode
was a three terminal device with a control grid that can modulate the flow of electrons from the filament to the plate. The triode vacuum amplifier was used to make the first AM radio. Early audio power amplifiers were based on vacuum tubes and some of these achieved notably high audio quality.

Thanks all for participating and please check the video for more details and practical representation of this primitive Audio Amplifier circuit i hope you will see the practical and simplicity of the project and not so the errors if you want more electronic projects visit NoSkillsrequired youtube channel.


ubergeeknz (author)2017-12-06

Should the capacitor not be in series with the output, rather than the input? To prevent DC bias from driving the speaker?

The gate to drain is isolated from source to drain

The voltage determines the conductivity of the mosfet. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals.

hubi (author)2017-12-06

This is no good design, since there is always a high dc current flowin through the speaker which will drain the battery rapidly and also is not good for the speaker.

NoskillsrequiredN (author)hubi2017-12-06

This is the simplest audio amplifier ever and current can be restricted,and with a 9v battery it draws 0.07A

gm280 (author)2017-12-06

Just to clarify what an amplifier actually does. First it doesn't MAKE anything. If that were true, we would have no energy issues ever. It merely allows you to control the supply power with a little signal at the input. In other words, you can control a large amount of available power with a little amount of signal. You can't make more output then the available power input. Once that is understood, amplifiers can be understood much easier. JMHO

NoskillsrequiredN (author)gm2802017-12-06

This is what i said in the first line of this AUDIO amplifier instructable its nothing related to the free energy concept, that's another topic my friend all the best

NoskillsrequiredN (author)2017-12-05

How to make a simple audio amplifier circuit

About This Instructable




Bio: Hello friends i show how to make stuff with no skills easy to replicate step by step from powerbanks,generator,invertors and so on thanks
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