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These 2 air horns churn out a loud warning with the deep sound you expect from a truck horn.
These 2 air horns churn out a loud warning with the deep sound you expect from a truck horn.
Get noticed with long, dual-horn trumpets. Corrosion-resistant coating. Deep sound. Really loud horn sound. Operates using a solenoid system.
Requires an air compressor or onboard air system up to 150 psi. Only comes with mounting hardware. No hoses or other accessories included.
A single-trumpet horn that blares a loud signal; comes with all the hardware and an air compressor for installation.
A single-trumpet horn that blares a loud signal; comes with all the hardware and an air compressor for installation.
Tough enough to withstand weather and last through years of use. Runs off a 12-volt DC power source. Portable, with the ability to take it from 1 car to another. Easy installation. Comes with hardware for mounting, as well as an air compressor and hose. Sounds up to 150dB.
It may not be as loud as expected. Doesn't come with power source or wiring for installation.
Some people think this 4-trumpet horn system compares to a train horn and is loud enough to scare others out of their lane.
Some people think this 4-trumpet horn system compares to a train horn and is loud enough to scare others out of their lane.
Very loud sound from the 4 horns. Comes with hardware, an air compressor, and hoses for installation. Horns hold up to cold weather conditions and years of use.
Can be difficult to install. Tone is higher pitched than expected.
This complete kit includes everything you need for installation outside of tools.
This complete kit includes everything you need for installation outside of tools.
It can reach a decibel count of 150 which is equivalent to a jet taking off. It can attach to any 12-volt vehicle, including boats and motorcycles. It comes in 3 colors.
Some found the wiring to be thin or otherwise average quality.
This air horn uses a 12-volt electric air valve.
This air horn uses a 12-volt electric air valve.
It has an attractive 4-horn design that’s chrome plated for plenty of shine. The chrome also protects against weather. It comes with screws and nuts, plus a bracket and 6 feet of quarter-inch nylon hose.
It requires an onboard air system to use.
We recommend these products based on an intensive research process that's designed to cut through the noise and find the top products in this space. Guided by experts, we spend hours looking into the factors that matter, to bring you these selections.
Updated August 2023
With roughly a quarter billion licensed drivers in the US, American roads have never been more crowded. To make matters worse, drivers are more distracted than ever. Studies have shown that distracted driving – especially as a result of cell phone use – is as dangerous as driving while under the influence of drugs or alcohol. And cell phones aren’t the only danger: radios, kids, GPS devices, and conversations can all contribute to distracted driving.
While distracted driving is dangerous in any situation, it’s especially dangerous when large trucks are on the road. Fully loaded, a semi can weigh as much as 40 tons, making it difficult for a truck driver to avoid a last-minute, tragic situation. Even worse, semis are much louder than the average passenger vehicle, making it harder for a trucker to get the attention of and alert other drivers. Because of these factors, many truck drivers use air horns rather than standard vehicle horns. Air horns are much louder and have distinctive tones that stand out in the noise of traffic.
If you’re in the market for an air horn, we can help. Our shopping guide and recommended products can point you in the right direction.
There are a number of factors to consider, both practical and legal, when choosing an air horn.
Many air horns use multiple horns, also called chimes or trumpets, to create their distinctive depth of sound. Each horn produces a different note that, when combined with the others, creates a chord. Air horns can have anywhere from one to five trumpets, producing a wide range of sounds. Many modern air horns include filters to help keep dirt, debris, and humidity out of the trumpets.
Because air horns are powered by compressed air, they have to be hooked up to an air compressor to function. Smaller units come with a small internal air compressor for ease of installation, while more powerful units tap into the air compressor that powers the truck’s air brakes.
Another thing to consider when shopping for an air horn is the noise level. Depending on the number of individual chimes, as well as whether it uses an internal or external compressor, air horns can produce sounds in the range of 110 to 150 decibels (dB). As a comparison, a lawn mower produces approximately 100 dB. It’s believed that a sustained noise level of 85 dB can cause hearing loss over time.
Trains use a larger, more powerful air horn to create the unique chords that locomotives are known for. As a result, train horns also produce more sound, usually in the range of 175 decibels.
Because of the loudness of the sound an air horn produces, many states have passed laws to limit the circumstances in which an air horn can be used. For example, in many states it’s only legal to use an air horn to give a warning. Any other use can result in significant fines. Many states and communities have laws prohibiting their use in population centers. Check your local regulations before you buy.
Air horns have a number of features you should consider depending on how you plan to use it.
Many air horn systems have compressors and air tanks that are designed to be stored inside the vehicle, safe from dirt, debris, and weather. Storing the system outside, somewhere on the chassis, will significantly shorten its life as dirt and water make their way into the compressor and damage it. If you need to install the compressor and tank on the outside of the vehicle, look for a sealed system. While more expensive, these units are designed to withstand outdoor conditions and will last much longer.
Many air horns are operated by pulling on a ceiling-mounted cord to open the valve and supply the horn with the necessary air to sound off. More modern systems have a button on the steering wheel like any other vehicle. In an emergency situation, the steering wheel button may provide faster response time.
The factors that impact the loudness of a horn and long it will sound are air pressure, air tank capacity, and duty cycle.
Air pressure: As a general rule, the higher the air pressure, the louder the volume.
Air tank capacity: A system’s air tank capacity impacts how long you can blow the horn. For example, a one-gallon tank at 150 pounds per square inch (psi) produces four to five seconds of sound.
Duty cycle: Similarly, the duty cycle of the air compressor tells you how long it can be used before it needs to rest, based on a 60-minute cycle. A compressor with a 10% duty cycle is able to run nonstop for six minutes before resting for 54 minutes. The longer the duty cycle, the longer you can blow the horn nonstop.
Because of the range of features and options, air horns vary significantly in price.
Inexpensive: Models that cost $50 or less are the most basic air horns on the market and focus on compactness over quality and sound. These horns have a single trumpet and are often small enough to be installed on cars and motorcycles in addition to trucks.
Mid-range: Air horns that cost between $50 and $100 represent a big step up in quality and sound. Many of these horns are advertised as train horns but are designed to be installed in a truck. Virtually all the products in this category include multiple trumpets and heavy-duty components designed to last.
Expensive: The air horns that cost between $100 and $500 are the best of the best. Horns in this category have multiple trumpets, sometimes as many as five. They’re made from the highest-quality, anticorrosive materials and are designed to operate under the harshest conditions. They also produce the richest, loudest sound.
In addition to the products we reviewed, there are a couple of other options that may work well for you. The Hurbo Super Loud Train Horns Kit is a four-trumpet air horn system producing 150 decibels of sound. It includes a 1.59-gallon air tank and pumps up to 120 psi. The tank and compressor are waterproof, making this a good option for exterior mounting. The Stebel Nautilus Compact Air Horn is an excellent, low-priced option. This horn is compact and works with any 12-volt system, making it ideal for installation on virtually any vehicle. It also produces a two-tone note, giving it a richer sound than many horns in its category.
Q. Are train air horns legal to use in a truck?
A. Yes, with caveats. Some states have laws prohibiting the use of train horns as a warning system and only allow them to be used as part of an anti-theft system. At least one state requires certification and only allows a train horn if it’s hooked up and powered by the air brake system. Other states allow them as a warning system as long as they aren’t used frivolously.
Q. How expensive are the fines for noise pollution or blowing the horn excessively?
A. Fines can vary from $75 to $1,000, depending on the state.
Q. Can I install an air horn kit myself?
A. Yes, in most cases. Air horn kits come with everything you need to install them, including instructions. As long as you’re comfortable working with 12-volt systems, you should be able to install it.
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