DIY Bluetooth speaker

Wireless devices have a number of advantages over conventional ones. One of the most significant advantages is mobility, the ability to take such a device with you on any trip. However, wireless speakers also have a high price, which makes their purchase impossible for a number of citizens. Then simple instructions for making a Bluetooth speaker at home with your own hands will come to the rescue.

REFERENCE! To manufacture such a device, you will need not only all the basic elements that will be listed below, but also basic assembly and soldering skills from the user.

What you need for work

Details

• To get full sound from the device, you will need speakers. In total, you should take 4 of them: two for low frequencies, two for high frequencies.

REFERENCE! It is not necessary to use exactly 4 speakers. There are options for a three-speaker build. One of them acts as a subwoofer, the other two are responsible for reproducing high frequencies. You can also use two identical speakers, which will not be separated in frequency.

• Crossover with two channels (2 pcs.).
• Two passive membranes.
• Battery.
• Charger.
• Amplifier.
• Bluetooth module.
• Boost converter.
• Power connector.
• Switch switch.
• Case material.

REFERENCE! The optimal material for assembling the case is plywood, since it is easy to obtain and easy to process.

Materials and tools

To make a homemade speaker you will need a number of tools and materials.

• Glue.
• A hacksaw, jigsaw and other tools for working with plywood or any material that will serve as a housing for the device.
• Marker, pencil and other items for marking.
• Ruler

Assembly diagram

As can be seen from the diagram, the speakers are connected via HF and LF pairs to the crossovers, which receive the signal from the amplifier. This was done to provide better sound quality to the device. To increase the sound quality of low frequencies, you should also install a low-pass filter between the crossover and the woofer, which will remove all upper harmonics, providing high-quality and deep bass.

Information from the Bluetooth module is sent to an amplifier, which is designed to pre-filter and amplify the signal. The amplifier module itself is powered by batteries (or rechargeable batteries). The voltage from them rises to 14 V and is supplied to the input of these two elements.

A protection board should also be placed between the supply voltage and the boost module, which will provide the device with short circuit protection.

A simple way to make bluetooth speakers

First of all, to manufacture such a device you will need a housing. The best solution would be to make it from plywood.

Important! When choosing the size of the case, you need to take into account that it must accommodate not only all the electronic components, including speakers, amplifier and battery, but also passive membranes.

Panels

On the front panel it is necessary to make holes for 4 types of speakers.A pair of large holes are intended for woofers. Smaller holes are needed for tweeters. The devices should be placed in pairs, a pair of LF and HF on the left and right.

The rear panel should contain passive membranes, as well as charging connectors and a power switch.

REFERENCE! The best material for gluing plywood parts is wood glue.

The side panels must be sealed and treated, since damage to their integrity will lead to a deterioration in the sound quality as a whole and the appearance of unwanted vibrations in the cabinet.

On the rear panel, as mentioned earlier, there are passive membranes that significantly increase the depth of the bass. They are not electronic devices and do not require inclusion in a circuit. The membranes are attached to the body with helium super glue.

REFERENCE! In order to reduce the body's own vibration, you should glue a couple of MDF strips. This will prevent unwanted sounds caused by panel vibration.

Assembly

After all the component parts of the case are ready, you should begin assembling the electronic components.

Nutrition

You should start with nutrition. If the voltage is supplied from batteries, an additional protection board will be required. Because lithium-ion batteries are very sensitive to both short circuit and overcharging.

IMPORTANT! Make sure that the voltage across all battery cells is the same. Otherwise, the device will work for a very short time.

Along with the protection board, the power switch should also be connected. When connecting the latter, the polarity must be observed, otherwise the device will fail. To check this, you should first connect the battery and check the voltage.

Bluetooth

The next step is to connect the Bluetooth module. This element has separate outputs for power and separate outputs for audio. The module itself already has both an ADC and a receiving antenna, so it will receive and process the signal itself. Power to the module will come from the protection board to special contacts.

REFERENCE! This element should be located in an accessible place so that the user has the ability to turn it on/off, as well as pairing and configuration at any time.

The Bluetooth module, in turn, should be connected to the amplifier via a step-up stage.

The signal from the amplifier will go to crossovers, the main task of which is to separate the sound into high and low frequencies. The corresponding speakers are connected to the corresponding output.

When all the elements are connected, they should be placed on the back panel. It is advisable that the wires do not cross each other. This may cause unnecessary interference that will affect the sound quality.

After all the parts have been placed, the front panel should be secured. The jbl portable speaker is assembled and ready to go.

Options for portable Bluetooth speakers that you can make yourself

There are many variations in assembling Bluetooth speakers. You can use not four, but two identical speakers, to which the same sound will be supplied. Such a device will have smaller dimensions, but the sound quality will be somewhat worse.

There are also variations of the build with two tweeters and one large subwoofer.

Whether a speaker is powerful or not depends on its components.

REFERENCE! The larger the size and power of the speakers, the greater the battery capacity will be needed to maintain normal operation of the device.

If the user needs a very small portable speaker, then such a device can be assembled using only one speaker. To do this, you only need the speaker itself, a battery (can be used from an old phone), a Bluetooth module, a charging module, an amplification stage and a power switch.

• First of all, you need to place the battery in the case. Connect the charge module to it, which is equipped with two LEDs signaling the charging process.
• The Bluetooth module and amplification stage should also be connected to the battery. The element to provide wireless communication must be connected via a power switch.
• From the Bluetooth component, the signal will be sent to the speaker through an amplifier. The module itself has corresponding outputs that should be connected, observing the polarity.

Useful tips

There are a few basic tips to keep in mind when assembling.

• Don't forget about grounding.
• Polarity must be observed. Otherwise the device will fail.
• The wires that connect the elements should be made as short as possible, and they should not intersect each other.
• The housing must be sealed, since if there are unintended holes, they can vibrate, creating an unpleasant sound.
• All essential elements must be easily accessible.
• The components must be securely glued to avoid damage during transportation.
• To avoid short circuits, all elements should be checked for polarity when connected.
• The main elements that are responsible for adjustment and configuration (Bluetooth module, power switches, amplifier with gain control) should be placed so that control of their parameters is comfortable. It is also necessary to take into account the possibility of replacing one of the components without having to completely disassemble the entire device.