DIY Bluetooth speaker. Homemade Bluetooth speaker

09.09.202327.05.2017

The idea of owning a portable Bluetooth speaker has haunted me for a long time. However, the price/quality ratio still did not reach a reasonable level, and still leaves much to be desired. There are excellent models on the market that deserve to be purchased, such as the JBL Voyager portable speaker. True, the price here is too high - about 220 US dollars. But you don’t really want to overpay just for a famous brand.

After all, in essence, all portable acoustics are ordinary multimedia acoustics + Bluetooth module + lithium-ion battery. And if you combine these components yourself, you can get a budget option that is quite good in quality.

Spring is in full swing. And the need for portable acoustics is now very relevant. After all, you can take it with you to a group of people on the street, or on a trip out of town for a picnic, or wherever you need mobility, but there is no outlet. In other words, you finally need to acquire such a gadget! But the desire to save money has not disappeared at all. Quite the contrary. This means it’s time to roll up your sleeves and do everything yourself. So, let’s define the goal - quickly, without much effort, from available parts, assemble inexpensive, high-quality portable acoustics that are not inferior to ready-made gadgets and are significantly lower in price. Let's get started.

Brief plan:

Select multimedia acoustics.
Select Bluetooth module.
Select a lithium-ion battery (portable charger).
Connect all this with blue electrical tape.
Profit. Enjoy portable music with friends.

Selection of components.

1. One of the most important characteristics of portable speakers, in my opinion, is size and weight. Based on these mandatory criteria, we will look for the most popular and inexpensive model of multimedia acoustics. Ok, google) After analyzing the characteristics, the choice fell on the Sven 315 speakers. For a price of about 8 US dollars, we get very compact multimedia speakers with high-quality sound. A huge number of positive reviews confirm this. (http://market.yandex.by/product/6226111/reviews?hid=91107&track=tabs)

Type 2.0
Built-in amplifier
Output power 5 W (2 x 2.5 W)
Lower limit of frequency range 100 Hz
Upper limit of frequency range 20,000 Hz
Height 70 mm / Width 70 mm / Depth 65 mm
USB powered

2. The next component is the Bluetooth module. A quick inspection of the sites www.dx.com and www.aliexpress.com found suitable modules for 6-7 US dollars (http://www.dx.com/s/bluetooth+audio+receiver+module). However, according to an ad on a local flea market website, there was suddenly an option that could be picked up tomorrow for $10. I didn’t really want to wait for packages from Chinese friends, so I bought what I had. My option (Bluetooth Music Receiver Adapter Dock Adapter Audio Stereo a2dp 30 pin)

This adapter is designed to connect to legacy docking stations with a 30-pin Apple connector. To pair newer i-gadgets (with a lightning connector) or Android gadgets via Bluetooth.

3. And the last component is the lithium-ion battery. Everything is simple here. Since our speakers are powered by a standard USB cable (5V), we take any portable charger with a USB output and a capacity no matter how much money you spare. (http://catalog.onliner.by/portablecharger/~fp=5v)
Here, the larger the battery capacity, the longer the music plays.

Assembly.

First of all, we need to disassemble the SVEN 315. I used the video instructions.

Then we disassemble the Bluetooth module and remove the board. This is only needed for my specific 30-pin model (for boards ordered from http://www.dx.com/s/bluetooth+audio+receiver+module this will not be required).

Having disassembled the speaker, we shorten the audio input wire and solder it to the Bluetooth module. We also branch and solder the +5v power supply from USB.

We secure everything inside with thermoplastic glue so that nothing dangles.

After installation you can check it. We connect the speakers via USB to a portable charger. And we pair it with the phone.

That's all.

We have created excellent budget portable speakers with which you can safely go on a picnic with friends.

Making a speaker that supports the Bluetooth Speaker wireless interface is easy and cheap. This idea will cost you no more than $14 dollars.

You may already have some components that you don't need to buy, such as 3-watt speakers.

In the following steps, I will try to offer the easiest way to assemble this Bluetooth speaker. Even beginners, I hope, will understand, since I myself did not have much knowledge of speakers, amplifiers and Bluetooth modules before making this speaker.

The portable speaker will provide long battery life if you use a 18650 lithium battery.

I used 3x 18650 lithium batteries in parallel. At the same time, the total capacity was 6600 mAh, which was enough to play music for 8 hours at the highest volume.

The portable speaker is charged via micro USB, which is very convenient!

Step 1: Selecting the necessary components

What do we need?
- Bluetooth stereo audio module
- Micro usb charging module 5 V, 1 A
- 2x3 W amplifier
- 2 speakers 3 W, 4 Ohm
These speakers had good reviews and sounded very good for their size!
- 3.7V 18650 lithium battery
- 100 µF capacitor
- Short wires and switch

Step 2: Assembling the circuit

Connect the components using wires as shown in the image.
It is best to glue the Bluetooth module to a printed circuit board. You can also add buttons to the module to adjust the volume, as well as buttons for pause, play and skip to the next audio track. But I did not install these buttons.

In the next video, I will test the speaker using an external power supply instead of a battery.

Step 3: Making the speaker housing

I initially wanted to make the body out of wood because it provides excellent sound quality.

But later I decided to place the device in a PVC case. For this I took a T-profile with a diameter of 50 mm. It was easier for me to make such a case, and it turned out to be quite original, moreover, compact and with good sound.

The word Bluetooth refers to the technology of transmitting data over a radio channel over a short distance of several meters, for communication between mobile phones, computers and other digital devices. The Bluetooth interface is characterized by low energy consumption and low cost. Currently used most often for communications between cell phones and wireless headsets. The Bluetooth radio interface was intended for transmitting data and voice messages.

In the traditional headset version, the Bluetooth module has a chip, a small 3.7V 50mA lithium-ion battery, a microphone, a speaker and a power button.

The low cost of the hardware, a good degree of protection and ease of use have made this standard very popular. Bluetooth uses frequencies in the region of 2.4-2.48 GHz and does not require licensing. Currently, the global industrial community has accepted this technology as a general standard.

The user experience that Bluetooth technology provides is sure to be hugely popular. Let's say, when you come to the office, your pocket computer is immediately automatically synchronized with your desktop PC, new contacts are transferred to your mobile phone, etc.

The Bluetooth module contains a forming, receiving and transmitting part of the equipment and built-in software. Communication between the module and the host controller is made using a high-speed USB interface or a UART/PCM interface. The host controller interface in the Bluetooth module is the command interface. The host sends commands through the IHC, and in response receives messages from the module about their execution; The communications manager sets up the required host controller configuration.

Bluetooth has two communication options: synchronous and asynchronous. The first type is designed to establish a symmetrical connection and is used for voice transmission. The information transmission speed is 64 Cit/s. The asynchronous version is designed for packet data transmission, the transmission speed is 720 Kbps. At the beginning of the block there is an access code, followed by a packet header containing the packet checksum and information about its parameters, and at the end an area directly containing the information being sent.

The diagram of one of the Bluetooth radio modules is shown below:

The frequency spectrum allocated for Bluetooth has a range of 2.402...2.480 GHz, which is divided into several channels. The bandwidth of each channel is 1 MHz. Channels are changed according to a pseudo-random law. Constant alternation of frequencies allows the radio interface to broadcast information over the entire range and eliminate interference from other devices. If this channel is busy, the system will switch to another, free from interference.

Discuss the article BLUETOOTH DEVICE DIAGRAM

DIY Bluetooth speaker? Yes, now I’ll tell you the easiest way to make Bluetooth equipment, which is quite popular nowadays, from your old home speakers.

Bluetooth speaker, how things are going

With the advent of Apple technology, I began to become quite interested in the technologies that are implemented in these devices, one of such technologies was AirPlay. The technology allowed you to stream audio and video to another device from your iPhone, iPad. The data was transmitted via Wi-Fi, which made it possible to maintain quality during transmission over the air. But there was one problem, this problem of all Apple devices - the price. Such speakers had a price of $300 and above, which discouraged the desire to purchase such a device, because the size of the speaker itself was quite small.

Later I thought that I have speakers at home, why should I overpay for new ones? I only need a device that will receive the AirPlay signal. After searching on the Internet, I realized that it would not be possible to “screw on” AirPlay, but it is possible to use Bluetooth and it will be much cheaper. First of all, I went to Chinese online stores, where I searched. Since I often ordered goods from AliExpress, this device was ordered from there.

The device does not have a brand, name or any other designations, but when connected it calls itself “BT310REV”.

Appearance.

As you can see in the photo below, the device is quite compact and will not get in the way in the car. Due to the fact that the kit includes an adapter, you can immediately insert one end of the adapter into the car radio, and the other end into the Bluetooth receiver. You can do the same with columns. Here you have a “DIY Bluetooth speaker”. The receiver is made of Soft-touch plastic in matte black color. This is an ideal option for this device; it is not noticeable, but at the same time it does not look disgusting.

Sound.

The sound of this receiver is 3.5 out of 5. The Bluetooth version is old, because of this the transmission speed is lower than it could be. Compared to a cable connection, the sound is quiet and there are noises, but if you turn it on on cheap speakers or simple tweeters in the car, I think you won’t notice any difference.

Device specifications:

Transmitter version: v3+EDR, Class 2 (Support A2DP V1.2 (built in Mic).
Power: charging from USB 5V DC.
Data transfer rate: 3 Mbps.
Transmission distance: up to 5 meters. Also catches behind a concrete wall.
There is a microphone.
Battery 220mAh. As stated, enough for 8 hours of work.
Works with all iOS and Android smartphones.

Contents of delivery:

bluetooth transmitter
3.5 mm stereo adapter
Micro USB charging cord
User manual in English

Using a Bluetooth receiver.

First, connect the receiver to your speakers.
Press the only button on it. Hold this for 3-4 seconds, after which you will hear a woman’s voice in the speakers and the blue indicator will light up.
Turn on Bluetooth on your device and connect to the receiver. Its name is "BT310REV".
Everything connected to the iPa without any problems, music played from any application in the system. The device's charge was also displayed in the status bar.

To turn off the receiver, hold down the button until the blue indicator goes out.

Personal opinion on this device.

The device is definitely needed and I really liked it. The appearance is attractive. The sound, although not perfect, is still better than it could be. Don't think that now I'm only praising the device. In fact, it is Chinese, with all that it implies. A large number of defects and, as you may have guessed, I also came across a defective copy.

How it happened: About 3 times I connected the receiver to different speakers and it worked, but the connection lasted no more than 5 minutes, everything was fine. I was just glad. But one evening I decided to test the device and connected it for a long time. He played for about 45 minutes and then the problems started. The signal began to be interrupted more and more often, and the hiccups of the music were heard. It felt like he simply didn’t have time to receive the signal, he was already receiving a new one and missing the previous one. This lasted 2-3 minutes, during which time I tried to stop the music, the receiver played again for a couple of seconds, but again began to interrupt. Those 2-3 minutes passed and all hell broke loose, an eerie squeaking sound mixed with ultrasound came from the speakers. The Bluetooth receiver did not reboot, I had to wait until the battery ran out. After completely discharging, the device worked for a couple of minutes and when I tried to turn it on again, it did not turn on again. At the moment it has not been possible to restore it.

But despite this, DIY Bluetooth speaker is ready, purchase devices of this type and use them!

Any speakers can be made into wireless speakers, the signal to which is supplied from a smartphone, tablet or computer using Bluetooth. For this DIY project you will need:

Any stereo speakers (for example, from an old stereo system).
- Amplifier with built-in Bluetooth module.
- Power unit.

The amplifier can be purchased on AliExpress or another similar site. High-quality amplifiers cost from $10 and above, and there are models on sale that consist simply of a circuit board, and others in cases with buttons for pairing with a sound source, controlling the volume and switching tracks. Models in cases are a little more expensive, but you don’t have to cut out the case yourself and look for buttons that fit the size.

You will need to connect a power supply (usually 12 volts) to the amplifier; they are sold separately and are often found on Avito and other online flea markets. To drive powerful speakers you need a power supply with a current of 2 or 3 amperes, and for small acoustics 1 ampere or even less is enough.

Connect speakers and a power supply to the amplifier, press the pairing button and establish a wireless connection with the sound source. If everything is in order, a signal will sound indicating that it is time to turn on the music.

14.02.2018

Technological progress is moving forward by leaps and bounds, now even preschoolers have a mobile phone and know how to access the Internet, and seeing a person talking to himself on the street, no one will twirl his finger at his temple - everyone is already familiar with a Bluetooth headset, which is a wireless technology. This transmitter operates using encrypted signals, which, in addition to convenience, allows you to protect personal data. The wireless module allows you to establish communication among several devices.

Many of the most modern models are already integrated, mainly to facilitate pairing with smartphones. Simply increase the distance between the audio source and the speaker and go, without having to search, enter menus, download configuration apps, or enter pairing codes.

As for the profile, the one supported by our presenter, one or the other will determine from the functions of the same sound quality that we can get. Both of them must be compatible with the same profiles to use them. It is most often used to receive audio content on headphones. . Other solutions are already there when some brands are loaded.

Bluetooth application

This device is now built into almost all cell phones and many laptop models. This allows you to significantly expand their communication abilities:

You can exchange various files (photos, videos, music) between phones, phone and laptop, communicator, camera.
The module allows you to connect any peripheral devices (wireless headset, headphones, speakers, video cameras and other gadgets) to phones or personal computers.
Talk on the phone without holding it with your hands.
You can create a wireless network between several of your PCs and other devices at home or in a small office, allowing you to have constant access to the necessary files from any device.
The Bluetooth adapter allows you to access the Internet by synchronizing your PC with your mobile phone.

That is, wireless devices are necessary not only for using a hands-free headset, but also facilitate communication between the computer and gadgets.

If we're already pairing them, it's more straightforward to start sending audio whenever we want without waiting. Reducing speaker size and weight usually results in reduced performance due to the use of different materials in both the cabinet and drivers. There will be details in the design of a wireless speaker that are usually appreciated such as handles or the ability to carry cases or carry them from one side to the other in a backpack without difficulty or undue inconvenience.

Technical requirements for consideration

If we intend to use the equipment frequently outdoors, it is strongly recommended to have a resistant profile so that it at least supports splashes of water and dust or sand, although there are models that can even be submerged and that they continue to work. There we will find many clues that will tell us about the paper.

How to make an internal bluetooth module for a laptop?

For an active person, it may be inconvenient to use an external Bluetooth adapter. Some craftsmen suggest modifying it with your own hands into an internal one by soldering the device to a USB connector. This option is suitable only for those who are familiar with a soldering iron and have experience in assembling and disassembling laptops.

Internal battery and speakerphone

Four main ones. Resistance This is the resistance that the system opposes to the passage of current and should be as low as possible as it will be a good indication of the overall quality of the equipment. Number of Channels and Size of Drivers In the world of speakers, although the number of channels is not a direct signal of the quality we will receive, they give us more options. Usually the point is that on the market we find 0 systems or here comes the size of the drivers, which are key when we talk about a subwoofer, for example. In small sizes there is not much opportunity to offer good bass reproduction, and this is where we can find some important differences. It should be wide. . Around 10 hours is the value we have to demand from our portable equipment and it should be taken into account that this autonomy figure is usually specified for using the speaker at 50% of its maximum volume.

Work on improving the gadget with your own hands is carried out in several stages:

If everything is done competently, the device should work.

Is it possible to make a wireless module yourself?

Sometimes the question is asked: is it possible to make a transmitter with your own hands? This option is quite difficult to implement. You cannot assemble a microcircuit with your own hands at home, since it is very miniature, requires very delicate work, and the selection of the frequency range is carried out using integrated solutions; the protocol has been developed by specialists for years.

When evaluating the purchase of a speaker with an internal battery, keep in mind the charging time and system used by each piece of equipment. To make sure that the equipment you purchase is loud, it is much better if the microphones carry some kind of technology to reduce ambient noise.

With new wireless transmission standards there has been significant improvement in this type of connection between devices. Already for memory, there were times when the quality of the sound transmitted with this system was very low. Nowadays, you can enjoy quality sound in a huge number of speakers of all kinds, which will adapt like a glove to your needs.

Therefore, radio amateurs can only use ready-made Bluetooth transmitters and modify them at their own discretion, adding the necessary elements to the finished circuit with their own hands. Some suggest upgrading a music speaker with a module or making wireless speakers, as well as adding a transmitter to the car’s audio system to avoid a clutter of wires and download your favorite music directly from the Internet.

Minimum requirements for any type of wireless speaker

Wireless technology is designed in such a way that the sound source can be located some distance from the speaker. For this reason, a series of buttons are built into the same speaker as volume, power, pairing button or track control, etc. They will give the complex additional comfort without allowing access to your smartphone, tablet or regardless of the sound source to make adjustments.

More than wireless connections

Having certain connections will give you versatility and expand the possibilities of use. Before you start your search, you should be clear about the use you will give the speaker. It doesn't have the same features and specifications as a speaker designed to remain stationary in your home, one designed to be worn all day.

The video below shows in detail how to do this. But in any case, such manual work requires good knowledge and skills in radio engineering, otherwise from one working Bluetooth module and additional elements you can get a set of disparate radio components.

The first and most important is the battery. To enjoy hours of musical entertainment, this is the basic battery that meets your expectations. The required minimum is approximately 8 hours of continuous playback, although some can reach as much as 15 hours of use.

Additionally, it is important to review your battery charge time information once it is depleted, as some devices may have excessively long charge times. Another important feature that a speaker for your smartphone or tablet should have is that it is lightweight and compact.

DIY Bluetooth speaker? Yes, now I’ll tell you the easiest way to make Bluetooth equipment, which is quite popular nowadays, from your old home speakers.

Bluetooth speaker, how things are going

In addition to the functions already mentioned, the main thing is to know the reception range of the loudspeaker. He believes that the further the speaker is from the sound source, the lower the reception and therefore the sound quality will be lost. Something very useful as they use the link already created between your smartphone and the speaker to conveniently answer your calls without turning off your music or taking your smartphone out of your pocket. When you receive a call, the pause player on your smartphone or tablet will be activated and the speaker will emit a tone.

When you end the call and end the call, you will play the music again at the exact point where you left off before the call. This will give you more peace of mind when it comes to carrying your speaker, as it is inevitable, when used outdoors, to get a little bumped or bumped, exposed to the humidity of a park lawn or the heat of a summer day.

Scalability is a very unusual feature among portable wireless speakers, but it's very useful in some cases and you'll be glad your speaker has this feature. This, for example, will allow you to join your presenter to your friend and quickly create a sound system 0 that will significantly improve the sound quality, or you will be able to expand the coverage area to cover a larger area.

The device does not have a brand, name or any other designations, but when connected it calls itself “BT310REV”.