Want To Change The Sound Of Your Car's Horn? Here's How It's Done

We may receive a commission on purchases made from links.

There are certain situations where a car horn comes in handy: to let someone know you've arrived outside their house, warn another motorist who is drifting into your lane, or let other drivers know how angry you are without having to strain your vocal cords. (Though bear in mind, a federal court has ruled that honking your horn isn't protected free speech, so you may want to exercise some restraint.) While the default sound is usually adequate, considering horns have been a fixture on automobiles for well over a century, some variety may be in order.

There are a few approaches you can take. You can swap out the horn (usually located behind the front grille) with a suitable replacement that fits your vehicle. Alternatively, you can craft a separate bank of various horn sounds, using a basic sound board, amplifier, button controls, and a speaker suitable for outdoor use. The first option is easier, since you're essentially swapping out one part for another. However, the sound bank does afford you the opportunity to get more creative, even though it's a bit more of a project.

While a car horn's operational lifespan can be quite lengthy, they're hardly immune from wear and tear. You could firmly press the center of the steering wheel only to hear a weak signal emanating from your car — or, worse, no sound at all. This is especially true if you're a frequent honker, which prompts us to ask the question: If I never honk my car horn, does that make me better than you? So there are situations in which replacing the horn itself is in order. In that case, you'll need a new horn from an auto parts store — one that fits your make and model — and a ratchet set.

To gain access to the old horn, you might need to disconnect the front grille, as this can provide easier access to the part. Once the grille panel is removed, look for a small circular part, and carefully undo the wires connected to it. Next, you should notice a bolt that's attaching the horn to the car. Using a ratchet, loosen the fastener and remove the old horn. Then attach the new horn with the same bolt, and reattach the wires. Once you reinstall the front grille, the project is complete.

If you want full customization, you'll need to construct your own bank of sounds, completely separate from your stock horn system. You can start with something like the Adafruit Audio FX Sound Board, which includes a stereo line out and a USB connector. You can plug your PC into the sound board via the micro-USB connector and drop audio files directly onto it.

For power, you'll need a 12-volt or cigarette lighter plug, the original car hack, and a 12-volt to 5-volt converter. While you can run 12 volts directly to an amplifier (which makes the sounds loud enough), that's too much for the sound board. So you'll need something like the Yipin Hexha DC 12/24V to 5V Converter, a small device that connects to the 12-volt plug and features a micro-USB for power, plugging into the sound board.

So you go from the 12-volt plug, using wire nuts to combine one set of red and black wires running to the converter, and the other running to a small amplifier. The amplifier plugs into the sound board's stereo out, and another set of wires runs from the amp into an outdoor speaker. 

To trigger the different sounds you'll need to wire some basic push buttons to the board. If you're using the Adafruit Audio FX Sound Board, consult resources like the Pinouts tutorial from Adafruit to help guide you. Then you need an enclosure to contain the wires and mount the buttons. Lastly, the speaker will need to be attached under the hood near the front of the car, and its wiring run to the enclosure through the fire wall.