If you are tired of the monotonous beep of your car, then check out this article. In it, a homemade master will tell you how to make a beep with many melodies for a car. The beep will play up to 83 sound melodies. The beep is controlled by a small control panel with 11 buttons. Three buttons are for programmed sounds, and the other eight buttons are “categories” of sounds, each of which stores 10 sounds. Each press of these last buttons will play a random sound from that category.
Unfortunately, the master did not provide a video of this particular device, but he posted a video of similar devices by other authors. To understand how it works, let's watch the video.
The heart of the system is the Adafruit Audio FX board. It does not require programming, and sounds can be recorded directly from the computer.
The Audio FX board is powered by a micro USB cable and outputs sound via a 3.5mm jack. It is fed into an inexpensive 120W amplifier supporting one or two speakers. They are 5 ”15W horns that fit easily into the engine bay.
Tools and Materials: -Adafruit Audio FX Sound Board;
Note that there are four variants of this board. This device requires a board with 16 MB of memory, a 3.5 mm audio jack on one end and a micro USB connector on the other.
-Siren speaker 5 inches 15 V – 2 pcs;
This 15W speaker is loud enough to be used as a car horn and small enough to fit in the engine bay. The master installed two horns for better overall volume. These speakers are also weatherproof. Note that these are speakers without bass. Simple sound effects will sound good, but rich music won't.
-TPA3116 D2 120 W + 120 W Two-channel stereo digital audio power amplifier 12 V – 24 V;
-Set of colored round tactile pushbutton switches – 15 pcs;
-Perforated board 83 mm x 33.75 mm;
Any type of punched board will work as long as it has a standard spacing of 2.54 mm (0.1 in.).
-Rectangular audio cable 3.5 mm;
-Micro USB cable;
-USB power adapter from 12 V to 5 V;
– Automotive splitter cigarette lighter 12V;
-7-pin JST sockets ;;
-Noise suppressor ;
– Micro USB cable – USB A;
– Single-core wire; < br> Step one: connection diagram
The device is powered by a 12V automotive socket. This socket provides power only when the vehicle is running or the vehicle key is turned to the correct position. This way, the car horn does not drain your car's battery when it is not working.
If your car does not have a cigarette lighter or socket, you can connect the device to the on-board network through the fuse box or, in extreme cases, directly through the battery.
Audio from the Audio FX board is routed to the ground loop isolator via a 3.5mm cable. This eliminates the noise generated by your vehicle's electrical system.
The horn (s) are connected to the amplifier. Each speaker comes with a long 3.5mm mono plug cable.
The control panel includes 11 buttons assembled on a circuit board. One leg of each button is ground and soldered to GND on the Audio FX board. The second legs of each button are soldered to pins 0-10 on the board.
Step two: panel assembly
The buttons and the Audio FX board are housed inside a 3D printed control panel. The STL files can be downloaded here.
You need to use ABS filament to print. This material will not melt from the sun. Printing with 15% coverage and no supports.
After printing, place the feet of the 11 pushbuttons in the perforations so that they line up with the holes in the control panel.
Note that the pushbuttons are not symmetrical, although they look. At the bottom of each of them are tiny letters engraved. Make sure the letters face the same direction for each switch. This is important for the correct alignment of the button caps with the holes in the control panel.
The eight pushbutton switches to the right of the control panel face the same direction. Of the three switches on the left side, the top switch needs to be rotated 90 degrees so that the entire board fits properly into the control panel.
The distance between the buttons is very small. This will cause the colored button caps to rub against each other. The buttons have tides at the bottom. They need to be grinded or cut off. After this operation, the buttons should move freely without jamming.
Step three: connecting the panel
The control panel has 12 wires connecting it to the Audio FX board. 11 wires for buttons and a 12th wire to ground.
Instead of running separate ground wires from each button to the Audio FX board, connects each button in series to a single wire.
You need to mount a 14-pin plug on the Audio FX card. Two 7-pin JST connectors will be attached to a 14-pin male soldered to the Audio FX board.
The next step is to solder the JST connector wires to the keypad. There are 14 pins on the Audio FX board. However, neither the first pin (RST) nor the 13th pin (ACT) will be used. Instead, the buttons will connect to pins 2-12 (when counting to the left), marked on the board as 0-10. The common ground of the buttons is connected to pin 14 on the board, designated as GND.
The order of connecting the buttons, as in the diagram below.
The micro USB extension cable connects to the connector on the left corner of the Audio FX board.
Connect the two 7-pin connectors to the Audio FX board, making sure the button wires line up with pins 0-10. Finally, attach the board to the control panel using three screws that go through the holes on the board.
Step four: preparing sound files
The Audio FX card reads audio files in OGG or WAV format. OGG file sizes are smaller and allow you to load more than 80 audio files onto the board. WAV files can take up about 10 times the space.
When used as a car horn, audio files should be relatively short. The wizard has sound effects from 7 to 18 seconds.
When downloading sound files from the Internet, it is likely that the volume of the files will vary. The wizard uses the free MP3Gain program to set all audio files to 100.0 dB.
Most sound effects are in MP3 or WAV format. The wizard uses the free VSDC Audio Converter to convert them to OGG format.
Sound effect files must have specific names so that the Audio FX board can assign them to specific buttons. The sounds assigned to the three “favorites” buttons on the left side of the control panel (triangle-shaped area) are named by the wizard:
T00.OGG T01.OGG T02.OGG
Note that the control panel has 11 buttons, but the Audio FX board assigns the first button a number “00” and the 11th button “10”.
Each of the remaining eight buttons on the control panel (two rows of four) can contain up to 10 sound files each. When one of these buttons is pressed, the Audio FX card will play a random file of 10 associated with that button.
For the first of eight buttons, the 10 sound file names are:
T03RAND0.OGG T03RAND1.OGG T03RAND2.OGG T03RAND3.OGG T03RAND4.OGG T03RAND5.OGG T03RAND6.OGG T03RAND7.OGG T03RAND8.OGG T03RAND9.OGG
For the second of the eight buttons, the 10 sound file names are as follows:
T04RAND0.OGG T04RAND1.OGG T04RAND2.OGG T04RAND3.OGG T04RAND4.OGG T04RAND5.OGG T04RAND6.OGG T04RAND7.OGG TOGG4OGRAND4.OGG
… and so on.
On the last button, the names are:
T10RAND0.OGG T10RAND1.OGG T10RAND2.OGG T10RAND3.OGG T10RAND4. OGG T10RAND5.OGG T10RAND6.OGG T10RAND7.OGG T10RAND8.OGG T10RAND9.OGG
Next, you need to download the audio files to the Audio FX card by connecting it to your computer using a micro USB cable.
Step Five: Checking the Audio FX Board
In this step, the Audio FX board should be connected to the control panel buttons through the two 7-pin JST connectors.
To test the board, connect a pair of PC speakers to a 3.5mm cable. Power the board with a micro USB phone charger.
When you press a button, a red light on the board turns on and the sound plays through the speakers. The next file can only be played after the red LED turns off.
If the red indicator does not light up when the button is pressed, the connection of the buttons on the control panel may be incorrect. Check if the connection is correct, the name of the audio files is correct.
Step six: turning on the control panel and amplifier
The device is powered by a car socket. Another option is to connect the device through a fuse box or from a battery.
Step seven: amplifier
The amplifier receives the audio signal from the Audio FX board, amplifies it, and then sends it to the speakers. While the Audio FX board requires approximately 5 V to operate, the amplifier requires a 12V supply.
For the amplifier, the wizard designed and printed a package. The file can be downloaded here.
Instead of attaching the signal and power cables directly to the amplifier, the master decided to add 2-pin male/female connectors to these cables. This way, you can easily disconnect the amplifier in the future if necessary.
On one side of the amplifier, there are two green speaker terminals. It doesn't matter which speaker is attached to which connector, the main thing is to observe the polarity.
The power input on the amplifier is another green connector on the same side of the board.
After connecting all the connectors, you need to adjust the volume of the amplifier.
The amplifier is designed for 100-120 watts per channel, but the speaker itself is designed for 15-25 watts. The amplifier has two potentiometers.
For optimum volume, use a small flat-blade screwdriver to turn both potentiometers clockwise until they stop. Then turn them counterclockwise 1/2 turn.
Next you need to find place and install speakers in the engine compartment. Pull the wires inside.
Connect the wires to the amplifier.