RC cars can get pretty loud. If you are new to RC Cars, this is probably one of the first things that got you worried, and at the same time, impressed. It is amazing to watch a small car make such powerful noise. However, loud noise can pose serious personal and social problems. But, first, why are RC cars so loud in the first place?
In general, there are several factors that can contribute to the loudness of RC cars. Brushed DC motors create a lot of vibration. Worn out gears and shafts make unwanted noise. And, the bodyshell of the car can act as a speaker box to amplify all these sounds. So, you have to understand the machine to detect the noise source.
Many RC car enthusiasts have held back from taking their RC cars out for some time because of the noise problem. With a proper understanding of the matter, you can easily solve this issue, so you can enjoy the great time you have when you are out with your RC car.
How Noisy Are RC Cars?
On average, an RC car can create up to 50-70 decibels of sound. That is roughly equivalent to the noise a vacuum cleaner makes. However, depending on the model, an RC car can be as loud as 100 dB or even more. Remember that any noise above 85 dB is considered harmful to the human ear.
A typical lawn mower produces around 90 decibels of noise. This is a good standard for comparison, because many RC cars can easily reach 90 decibels after driving around for a while. For more comparison, heavy traffic noise ranges from eighty to ninety decibels.
Some RC cars, with faulty parts, create noise up to a hundred decibels or past that. It is generally known that sounds above 110 dB are painful for the human ear and can cause serious damage to your hearing ability. So, the noise can become a serious social and health issue if you do not take care of it at the right time.
Keep in mind that the variations in decibels are not exactly arithmetical. Although 100 decibels appears to be only 30 decibels higher than 70 dB, it is actually eight times louder. So, you have to be careful how loud your RC car is.
The Reason RC Cars Are So Loud
The reason behind the loud noise of the RC cars’ engine are electromagnetic forces, known as Maxwell forces. Well, other forces contribute to the noise too. Magnetic constriction forces, for example. However, the effects of these forces are not significant compared to the Maxwell force.
An electric motor, like the one inside your RC car, is a machine that runs essentially by manipulating electromagnetic forces. The parts inside an electric motor vibrate by electromagnetic forces such as the Maxwell force. When the vibrations are in audible range, they create noise.
The noise depends on the type of motor used. Take the generator of the wind turbine, for example. The magnet drives directly at low speed and high torque. As a result, they create only a low-frequency humming noise.
On the other hand, consider the brushless DC motor used in a typical RC car. It drives at high speed. The torque is comparatively low. Therefore, it creates a ‘high frequency’ noise that is unpleasant to the human ear.
Apart from the electromagnetic force inside your RC Cars motor, maintenance issues can be another cause of loud noise. If you haven’t oiled, changed, or cleaned your gear in a while, it can result in unwanted noise when you drive your RC car.
The Ill-effects Of Loud RC Car Noise
The loud noise from an RC car can become a pretty serious issue. The problems arising can be both physical and social. If you ever thought, “What’s the big deal? It is just a little noise,” try to consider the following.
Noise above 85 dB is damaging to our ears. Prolonged exposure to such degrees of noise can result in long-term hearing defects.
A typical RC car that creates around 65 dB can reach these extreme decibels after several drives in rough terrain. When you are driving your RC car, you probably will not mind the loud noise due to the fun and excitement you are having at the time. But in the long term, these prolonged exposures can give rise to hearing problems.
See my related article: What is the quietest RC car?
Moreover, there are some immediate effects too. You might experience headaches, dizziness, or a ringing sensation in your ears after you return from a session with your loud RC car.
Any sound that passes 70 dB causes discomfort to humans. When it reaches the upper limits of 100 dB, the sound becomes unbearable. At that point, people are bound to react to the source of that noise.
Your RC Car session can very easily turn into an unpleasant experience if you are not mindful of the noise. Worse than an angry neighbor coming to teach you a lesson is reporting you to the law and filing a formal noise complaint. You might lose the privilege of driving your RC car altogether.
Loud noise is also an indicator of decay. Maybe the motors have run out. Or, the gear teeth have become too sharp or blunt. Whatever the reason, if you let the loud noise continue, you are just promoting further damage to your machine.
Tips To Quiet Down Your RC Car
The noise is a part of the RC Car experience. So, you can never really make it completely noiseless. However, you can take measures to quieten down your car just enough so that it does not hurt your ears or cause any trouble with your neighbors.
Use A Silencer
Using a silencer or a muffler for the engine is one of the most popular ways of reducing noise. The silencer dampens the noise by cutting down the emitted sound pressure. Moreover, it makes the sound waves work against each other. Thus, it cancels them altogether.
Foaming The Bodyshell
The bodyshell of the RC Car acts like a speaker box. It amplifies the sounds created by the motors and gears. One way to take care of this is by using some foam isolators. These are essentially little pieces of foam that can stick to the inside of the bodyshell. Put them in your RC car and you will significantly cut down on the noise.
Use Adequate Lubrication
Greasing things up can help with your car’s noise as well as its performance. The drivetrain of your car comes all greased up when you buy it. But over time, the lubricant wears off. So, apply some lube to the drivetrain before each session.
The driveshafts and universal shafts will need greasing too. When these shafts become too dry, they contribute to the overall noise your car makes. Apply a dry lube so that it does not attract dust.
See a range of lubricants here, on Amazon
RC cars need replacements every once in a while. If your machine is making too much noise it is a good indicator that some of the parts need changing. You can always replace the motor with a less noisy variant. The drivetrain, driveshafts, and all other parts can be replaced from time to time.
Metal gears are so much better than standard gears, but they generally tend to create more noise. Your car might be in good condition but still noisy if you use metal gears.
Electronic Speed Controller
An electronic speed controller (ESC) is a small circuit board that you can fit into your RC car. The ESC will maintain uniformity in speed and keep your car stable overall. It is a good technique to keep your machine in top condition for longer periods.
Well, you now know how to keep your electric RC cars quiet. But what about Nitro cars, which can be way louder? See my article on how to make your nitro RC car quieter
Are Brushless Motors Quieter?
Brushless motors are made to work in environments that require noise reduction. So yes, these motors are quieter compared to brushed motors.
A brushed motor is noisy mainly due to two reasons. The brushes and commutator inside the motor vibrate and arc when the motor is running. Plus, whenever the current switches, it causes some vibration in the armature. Both of these factors contribute to the loudness of a brushed motor.
On the other hand, a brushless motor doesn’t have any brushes or commutator. The current switches over, more smoothly. As a result, there are fewer vibrations overall and less noise.
See a huge range of top quality Brushless motors here, on Amazon
So, why are RC cars so loud? RC cars are not toys. They are small-sized versions of real vehicles. The construction of the cars are similar to full scale cars. So, just like real life sized vehicles, if you take care of and maintain them properly, the noise can be kept to a minimum.