About: time passing when in mood, do crazy stuff with friends and occasionally with gaming stuff and arduino and beagle bone

How many of u wanted a loud sounding speakers even though u don't have enough money?

What if u can create ur own loud sounding speakers from scratch for a quarter of the price of a loud speaker?

Amazing right!! and u would even have the fun, cz u made it on ur own!!


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Step 1:

we will be making 2 types of amplifier's

> using Wireless Digital Bluetooth 4.0 Audio Receiver Amplifier Board TDA7492P 50W+50W(ready made)

but will take u time cz it ships from China

> using LM 358

Step 2: Wireless Digital Bluetooth 4.0 Audio Receiver Amplifier Board TDA7492P 50W+50W

required things

>Wireless Digital Bluetooth 4.0 Audio Receiver Amplifier Board TDA7492P 50W+50W - $10

(with case and screws)

> speakers (ur wish) x 2 i used 8 ohm speakers (classy looking ones)

> dc jack

> 15v power supply

Step 3:

before connecting the power make sure u push the push button (in the picture its to right of the captions)

and then keep the 2 slider buttons to off (mentioned in the pic)

connect the 15v supply to the board using the dc jack

and then ur ready to go

Step 4: Using LM358

LM358 Low Power Dual Operational Amplifiers General Description

The LM358 series consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a singlepower supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply voltage.Application areas include transducer amplifiers, dc gain blocks and all the conventional op amp circuits which now can be more easily implemented in single power supply systems. For example, the LM358 series can be directly operated off of the standard +5V power supply voltage which is used in digital systems and will easily provide the required interface electronics without requiring the additional ±15V power supplies.

Step 5:

Unique Characteristics

>In the linear mode the input common-mode voltage range includes ground and the output voltage can also swing to ground, even though operated from only a single power supply voltage.

>The unity gain cross frequency is temperature compensated.

>The input bias current is also temperature compensated.


>Available in 8-Bump micro SMD chip sized package

>Internally frequency compensated for unity gain

>Large dc voltage gain: 100 dB

>Wide bandwidth (unity gain): 1 MHz (temperature compensated)

>Wide power supply range: Single supply: 3V to 32V or dual supplies: ±1.5V to ±16V

>Very low supply current drain (500 µA) — essentially independent of supply voltage

>Low input offset voltage: 2 mV

>Input common-mode voltage range includes ground

>Differential input voltage range equal to the power supply voltage

>Large output voltage swing

Step 6:

Step 7: Schematic

Circuits Contest 2016

Participated in the
Circuits Contest 2016

Amps and Speakers Contest 2016

Participated in the
Amps and Speakers Contest 2016

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    3 years ago

    Have you actually built the LM358 version? That's a low powered op-amp, doesn't have the power to drive speakers (maybe some stupidly hi impedance ones very quietly, but it would sound bad). The circuit/parts list you've copy/pasted is for a pre-amp too, not a power amp. Don't want to sound negative but think some more details are needed to clarify what this circuit is about.