Audio Amplifier Project

The purpose of this project is to learn how to create an audio amplifier that are created by assembling various subsystems. This is a makers project. Your main goal will be to use soldering to construct the audio amplifier system and Fusion 360 to design the housing.

PAM8610

This digital power amplifier board consist of the main integrated circuit, the PAM8610 with various capacitors and resistors to complete the design. This board cost about $1.50 from Aliexpress.

Technical parameters

Power Supply:

Supply voltage - DC 6V-15V. Recommendation voltage: DC12V 2A
Standby current - 20mA

Speakers:

Output power: 10W * 2 (8Ω) 15W * 2 (4Ω)
Channel type: Double Channel
Output Impedance: 4-8Ω

Other specifications:

SNR: 90%
Working mode: Class D Amplifier
Frequency range: 20Hz-15KHz
Input impedance: 15K
Amplifier board size: 28mm * 22mm * 2.5mm

Speakers

Speakers are used to convert an electrical signal to an audio signal.

This is a simple design of a speaker, and it shows the working parts.

We provide electricity to the coil which vibrates back and forth. This is because when a coil is electrically charged it becomes an electromagnet.

Depending on the controller the coil is repelled by the permanent magnet moving the coil and cone back and forth in specific ways causing sound to be produced. The polarity of the coil is constantly reversing via the positives and negative charges on the coil swapping.

When the voice coil is moving back and forth it pushes the diagram back and forth creating the sound waves. The system is designed to move via a supportive suspension.

The speed and rate of the diaphragm makes the sound come out in different ways depending on the sound needed. This is all depending on the controller and how the coil is charged.

Other parts of the speaker

Dust cap – Protects sensitive electrical components from dust
Cone, surround and spider – these are the parts that hold the cone in place while still allowing them to move
Voice coil – The electromagnet that moves
Basket – Provides a structural base for the whole speaker
Top plate, pole, and rear plate – Surround the permanent magnet to focus magnetic waves
Magnet – The permanent magnet

Oval Speakers

These are the speakers we are using and the dimension for you Fusion 360 design is on the right.

There are rules for designing speaker boxes to get optimum sound. These websites are some starting points for the information you need:

Use this laser cut file for a start box. It a Lightburn file .

Bluetooth Audio Receiver Board

The receiver consist of a Bluetooth antenna to pick up audio from your phone via Bluetooth. The output is the left and right channel.

Very important to understand that the supply voltage is limited to 3.7 to 5V.

Voltage Regulators

A voltage regulator is a component that maintains a constant voltage at the output. Normally lower than the input voltage. This component allows for a larger power sources to be limited so that specific parts that require lower voltages don’t get damaged.

Why does our project need one?

We plan to use a 9v battery to allow our system to be portable but a 9v battery might damage the receiver system. Electronic components are only rated to be able to handle a certain level of voltage, because of this we need to be able to reduce the voltage to 5v therefore we will use a voltage regulator because it guarantees that only 5v will be given to the system.

We have chosen to use a 78L05 Voltage regulator (image to the left) due to it not only outputting the necessary 5v but also has a maximum current of .1 amp or 100 milliAmps. Due to the receiver only using about 20 milliAmps this will provide plenty of current that might be needed.

Input voltage range: 7 to 30V.

Extra Information on voltage regulator:

Wiring Diagrams

Fusion 360 Designs for your Audio Amplifier Housing

Extra Resources

Page updated

Report abuse