RMS means the safe and average amount of power you can use for your audio system for a long time without damaging it. Using this amount of power will keep your audio system safe and working well even after many hours of use. It’s the most important thing to consider when choosing speakers and amplifiers.

Don’t be fooled by the peak power rating, as it’s usually just hype. I can also help you match your amplifier with your speakers or subwoofers and share tips on how to get the best match every time.

What is RMS power rating mean in Speaker? An amplifier, or “amp,” is a device that increases the strength of an audio signal. A guitar amplifier, for example, takes a weak signal from a guitar and makes it strong enough to drive a speaker. The “rms” in “rms power” stands for “root mean square.” Rms power is a measure of the amount of power that an amplifier can produce


Root Mean Square (RMS) is a mathematical term that finds the average of a group of numbers. To calculate RMS, you square each number, find the average of those squares, and then take the square root of that average.

It’s also called a quadratic mean and is a type of average that emphasizes larger values more than smaller ones. When applied to waveforms, the RMS is a way to measure the power or loudness of the signal. Essentially, the RMS is the square of the average value of a waveform over time.


Here are the steps you can follow to find the Root Mean Square of a set of values:

Step 1: Multiply each value by itself to get its square.

Step 2: Add up all the squares and divide by the total number of values to get the average.

Step 3: Take the square root of the average to get the Root Mean Square.

You can also use a Root Mean Square Calculator to simplify the process.


The Root Mean Square formula helps calculate the RMS value of a set of data values or a continuous function over a specific time interval.

For a set of n values, the RMS formula involves squaring each value, adding them up, dividing by n, and then taking the square root of the result.

For a continuous function defined over an interval, the RMS formula involves finding the area under the curve, squaring it, dividing by the length of the interval, and then taking the square root of the result.

The RMS of a periodic function is equivalent to the RMS of a single period of the function. You can also estimate the RMS value of a continuous function by calculating the RMS of a sequence of evenly spaced entities. It’s also possible to calculate the RMS value of different waveforms without using calculus.


Root Mean Square Error (RMSE) is a way to measure how well a model or estimator predicts values. It is used to compare the predicted values to the actual values in a set of data. The RMSE gives an idea about the spread of the errors between the predicted and observed values.

When we calculate the RMSE, we look at the differences between the predicted and observed values. These differences are known as residuals if we calculate them over the data sample that was used to estimate, and prediction errors if we calculate them outside the sample. The RMSE takes into account the size of these errors and provides a single measure of how well the model or estimator is predicting values over time.


RMS Power Ratings: The RMS power meaning is defined as Root Mean Square which is a statistical way of representing DC voltage or AC voltage. Instead of using peak values, it uses average values thus giving you a better idea about its true performance and power handling capability.


Building the perfect audio system is an expensive hobby that has kept audiophiles busy for decades. As technology advances, this hobby becomes more addictive. However, one technical term that many people may not understand is RMS. It is an essential term to know if you want to build a high-quality audio system.

Audio technology can be challenging to comprehend, particularly for beginners. To build the ideal audio system, you need to have a good understanding of several terms. RMS is one of the most critical terms that you need to consider when buying new speakers and amplifiers.

RMS is crucial in ensuring that you get the best out of your audio system. In experienced speaker buyers, RMS is considered the most important metric that needs to be taken into consideration when purchasing new equipment. In this article, we will break down what RMS means, why it’s important, and how it fits into the overall audio system.


RMS in speaker means, power refers to how much continuous power the speaker can handle. For example, a 50W RMS rating but 70W peak means that the speaker can comfortably run with 60 watts of continuous power, occasional bursts up to 100 watts.

More often than not an amplifier’s RMS power ratings are grossly inferior to what it can actually handle. This is because manufacturers would want you to think that their amplifier has a maximum input power rating of, say, 1000 watts which may just be the peak or transient power it can handle. Manufacturers often measure RMS voltage by using a “burst” signal consisting of an extremely short duration (usually 10 ms or less) sine wave.

Such a signal will be able to produce higher output than a sustained sine wave, but only for a fraction of a second. To determine an amplifier’s maximum RMS output capability the “burst” signal is applied until it reaches its mechanical or thermal limit (when there is too much heat being produced).


The proper way to measure RMS is to apply a continuous sine wave at the amplifier’s rated impedance and measure its output voltage. This way, you are going to get the true RMS value of that signal which has a lot more credibility than taking the peak or burst reading.

Measuring at different impedances would lead us to quite interesting results: if it were at 4 ohms, the RMS power would be quite a bit lower than if it were at 2 ohms. This is because voltage doubles when the load impedance halves so you have to produce twice as much voltage in order to get the same output.

Although we are talking about doubling or halving of output power here (or four times or half as much power when the impedance quadruples), the resulting difference in volume is hardly noticeable. The reason is that our ears’ sensitivity to loudness doubles or halves with every 3dB increase and decrease of volume respectively (I have explained this simply here). This means, an amplifier with a maximum output of 100 watts per channel at 4 ohms should be able to deliver a maximum of 200 watts per channel at 2 ohms, and so on with other impedances.

If you would like to read some more on power ratings I recommend All about Power.


Dyno: an abbreviation for Dynamometer which is basically equipment that measures the amount of torque or horsepower being delivered by the engine to the driveshaft. It can also be used to determine the power requirements needed for an electric motor to achieve a certain speed and vice versa when used in conjunction with an alternator.

A dynamometer is basically a specially built drum that rolls instead of rotates due to its eccentric load which simulates real road conditions better than an engine dyno. An engine dyno, which is also called a “rolling road”, has the load on its drum either statically (by adding weights) or dynamically through a real gear and belt system plus dummy shafts and flywheel to match what a car would be running at its normal speed.


The only difference between an electric motor dynamometer and one for internal combustion engines is that the former has an electric motor connected to its output instead of a mechanical load while the latter simulates a car’s drivetrain by matching belt and pulley ratio with that of the engine.

More often than not, you will find both types used together in order to get more accurate readings on specific components like the alternator, transmission, and battery.

A gauge is a device used to indicate the value of some characteristics like temperature (thermometer), pressure (barometer), speed (speedometer), and so on. There are also gauges for electrical systems that indicate voltage in volts and current in amps using needles or LEDs instead of lines or marks like regular analog gauges.

Just like output ratings, there are a lot of different means to measure voltages and currents in order for manufacturers to advertise their equipment’s capabilities but the only proper way is by using steady state sinusoidal AC waveforms at rated impedance as explained above. The voltage should be measured across the positive and negative terminals of the AC power source and the current is then measured in between those same terminals.

This way you get RMS values which are far more accurate than reading it off an ordinary voltmeter or milli meter, especially when measuring high voltage AC lines or heavy-duty audio amplifiers where the presence of harmonics (which don’t count for much) would be very minimalized at best.

A load is any device that consumes current (or power) from an external source, in our case, an electric motor or a battery-operated consumer electronic device like the radio. When you use batteries with your car’s audio system it acts as a resistor and such resistance is what we call “load” when talking about electrical systems.


A way to determine how much power is needed for a specific amp in order to run it at its full potential (which would be different from one amplifier to another due to design and implementation) is by measuring the current or voltage in the system while playing music through it. The more current/voltage you measure, the more power is being drawn from the source.

Here’s a quick explanation of how to do it:

  1. Connect your voltmeter across the positive and negative terminals of your battery (or power supply). This will measure the voltage across the whole system which includes wiring, amplifiers, speakers, etc.

  2. Play music through your amp with an input level meter (or a voltmeter set to its highest scale) and take note of the voltage across the system with the characteristic frequency response (bass, midrange, and treble).

  3. Divide the lowest voltage by your maximum current measured in step 2.

  4. Multiply this fractional number with the rated RMS voltage of your battery or power supply.

Example: If your lowest voltage across the whole system measured was 11.5 volts at 100 Hz with a maximum current of 2 amps, then you will need a total power capacity of 32 watts. Since this is a fractional number that cannot be used directly to calculate the current draw, we multiply it with 12 volts (RMS) which gives us an answer of a 38 amp current capacity.

  1. Always be sure to measure voltages and currents with the system running at full power. This means that you should play your music at a high level from beginning to end without stopping for any reason (to avoid momentary voltage drops).

  2. Use a resistor matching the amplifier’s impedance in order to simulate a load when measuring voltage (ex: for 2 ohms use a 1-ohm resistor).

  3. Never disconnect or remove anything from the system while it is on. Doing this will damage your equipment if not done properly and could also be fatal, especially on car audio systems.

  4. We don’t recommend the use of cheap multimeters for this application. Good quality ones like digital oscilloscopes with well-shielded probes should be used in order to not alter the voltage being measured by acting as a current path.

  5. Don’t measure the voltage when the engine is running unless you know what you’re doing. It’s also good practice to disconnect the negative terminal of the battery when working with high voltage coils (ex: the one on your spark plug).

Related: 7 Signs of a bad car amplifier-Guide

The resistance of a speaker coil in an audio amplifier can be anywhere from 0.5 ohms to 8 or 16 ohms depending on many factors but mostly on impedance and power handling. A wiring diagram is included below as an example of how to hook up an amplifier. Always be sure that your amp can handle the total load (which includes wiring, speakers, and a resistor if used for simulating a load) by checking RMS ratings in its specs sheet.

On the other hand, an oscilloscope is required when measuring current on car audio systems because of several reasons: one being that it’s much easier to control voltage than current (you can always directly measure it with a voltmeter but not the other way around) and the fact that we need an accurate voltage reference in order to calculate how much power is being drawn from the source.

In this case, simply connect an oscilloscope probe across the + and – terminals of your battery. You should read a Sine wave with some sort of DC offset (the amount depends on your current draw). The average voltage of this sine wave is the RMS voltage, and multiplying this number by 1.4 will give you the peak-to-peak value which you can then use to calculate total power in watts with Ohm’s Law using the formula P=VI.

This method is not perfect since it only gives you an accurate power reading at a certain frequency but this will work just fine in our case because bass frequencies are the ones more affected by impedance changes on your system.

One final note: It’s possible to damage your speakers if you use an amplifier that has too much power for them. This is easily avoidable by making sure your amp does not exceed 1% of its RMS power into 4 ohms (ex: a 450W RMS amp into 4 ohms will never draw more than about 1.35 amps). Also, it’s a good idea to get speakers that handle double the power of what your amp can produce (ex: for an 800W RMS amplifier get speakers rated at 1600W or higher) because this will give you more headroom.


Manufacturers want to sell as many products as possible, and while they don’t intentionally make low-quality products, they do use big numbers to excite customers.

Many customers don’t understand the different metrics and numbers used to measure speaker performance. For these customers, a higher power output number may seem like a more powerful speaker.

Manufacturers often emphasize peak power output as the main metric in their product descriptions and marketing efforts because many consumers are attracted to big numbers.

While peak power output is useful to match with the power output of your amplifier, it is not the figure that represents the true power of the speakers you want to buy.

Therefore, you should not rely on peak power output as the main metric and should consider other important factors as well.


RMS is a measure of how powerful an electric current is, and higher RMS usually means louder sounds. To get the best sound quality, you should use a subwoofer with an amplifier that has an RMS power rating of at least 100 watts. When the RMSE value is low, the predicted and observed data are more accurate.

To get the best sound from your subwoofer, place it close to a wall facing outward. You can use speakers rated at 100 watts or more with a 50 watt per channel amplifier. A subwoofer with lower electrical resistance will produce louder sound than a subwoofer with higher electrical resistance.

The sound of an Ohm subwoofer can be louder and clearer with a low-end response, made up of four Ohm subplates. The performance of the subwoofer will depend on how well the rest of your audio system works.

If you’re using a speaker with a 1000 Watt rating, it’s better suited for hosting a party than as a home speaker because it’s too loud for regular use. A 12-inch subwoofer will produce a deeper sound. For a good sub, 150 watts is often enough. Some of the best 10-sub sets only have a size of 175 watts.

It’s recommended to have at least 120 watts RMS for peak power. Lower power ratings are suitable for systems with low power requirements, while for moderately high-wattage systems, you can choose between 150 and 200 watts RMS. If you’re using a higher-wattage system, increase the power to 250 watts RMS.


RMS ratings are important to know because they tell you how much power a speaker can handle without affecting sound quality or causing distortion. Higher RMS ratings mean that the speaker can handle more power and play louder and clearer. To see a noticeable change in volume, you would need to increase the power by two meters for every 3dB gain.

The closer the observed data is to the simulated data, the more accurate the simulation is. This means that a lower RMSE value is better for evaluating how well a model performs.

RMS and peak watt ratings are both important for your sound system. When you compare your speakers to amplifiers or subwoofers, understanding both RMS and peak watt ratings will help you make better decisions.

The recommended RMS wattage for speakers depends on various factors such as the size of the room, the type of music or sound being played, and personal preference. As a general rule, a good RMS wattage for home speakers is between 20 to 200 watts per channel.

For larger rooms or outdoor settings, higher RMS wattage may be needed. It’s important to match the RMS wattage of the speakers to the power output of the amplifier or receiver to prevent damage to the speakers.


To power a subwoofer with 200 to 300 watts RMS, you may need to get an aftermarket receiver. If you have a high-amplification speaker with around 50 watts RMS per channel, you can choose a system with 250 to 500 watts RMS. For the subwoofer, it is recommended to use a maximum power rating of 100 watts RMS per channel system.


Understanding RMS and its importance is crucial when upgrading or installing a new car audio system. Relying on peak power outputs when choosing individual components like speakers, subwoofers, and head units is not recommended, as these numbers do not reflect the product’s true capacity for continuous daily use. Therefore, it’s best to configure your system based on the RMS ratings to ensure reliable performance.

People sometimes think that manufacturers increase their RMS and peak power ratings to attract buyers, but that is not true. Products that undergo CEA testing are tested with the same equipment and procedures. Therefore, the RMS rating is usually accurate.

It is important to match the power output of your amplifier with the power rating of your speakers and subwoofers to get the best sound quality. However, many manufacturers don’t mention that most speakers can handle slightly higher RMS than they advertise.

So, as long as your amplifier matches between 75% to 150% of the advertised RMS of your speakers, you should have no problems with them. Remember, the speakers that you purchase will only perform as well as the amplifier that feeds them.

The most important advice from this article is to ensure that your amplifier provides the same amount of power as the RMS of your speakers and car subwoofers.

This will reduce the risk of your equipment failing and give you confidence that your system is working efficiently for long periods without any problems.


The RMS power rating of a device, such as a speaker or amplifier, can be affected by a variety of factors, including impedance, sensitivity, and frequency response. Here’s a brief overview of each factor:


The impedance of a device refers to its resistance to the flow of electrical current. The impedance of a speaker, for example, can affect its RMS power rating, as speakers with higher impedance require more power to achieve the same volume level as speakers with lower impedance.


The sensitivity of a device refers to how efficiently it converts electrical power into acoustic energy (i.e., sound). Devices with higher sensitivity require less power to achieve the same volume level as devices with lower sensitivity, so sensitivity can have an impact on the RMS power rating of a device.


The frequency response of a device refers to how well it reproduces sound across different frequencies. Devices with a wider frequency response may require more power to achieve the same volume level as devices with a narrower frequency response, as they need to produce a greater range of frequencies.

Overall, the RMS power rating of a device is influenced by a complex interplay of factors, and it’s important to consider all of these factors when selecting equipment for a particular application.


Q:1 What is RMS output?

RMS (Root Mean Square) is the preferred method of obtaining power measurements for audio signals. The idea behind it is to give you an idea of how powerful your sound system will be perceived by the audience/listener.

This means that the human ear perceives lower sound levels than what they are actually exposed to. For example, a 1 kHz sine tone at 0dB (RMS) is about 94dB. If you play this tone through your sound system, it will be perceived as loud as the actual 94dB level.

Q:2 What is a good RMS for speakers?

A speaker’s RMS is the electrical resistance of the speaker, which reveals how efficiently it can push air to create sound. A 4-ohm speaker will play louder than a 2-ohm one of the same power. The most common speakers are 8-, 6-, and 4-ohm models, but audiophiles may want to look for lower numbers – some quality speakers are 2 ohms or even 1 ohm!

Q:3 Does a higher RMS mean louder?

The sound’s volume is a function of the square of the RMS amplitude. So if you double the power of a device, it doesn’t necessarily mean that you will hear everything twice as loud. In some instances, you may only get an increase in output by 6dB which would be below the normal threshold of hearing sensitivity and unable to diagnose hearing loss.

Q:4 What is speaker RMS vs peak power?

The RMS power handling of a speaker tells you how much power it can handle continuously. On the other hand, the peak power handling value refers to the highest power level the speaker can handle for short periods of time.

Q:5 Does RMS matter for speakers?

RMS values indicate the actual capacity of a device to handle power, which is usually lower than peak watt ratings. RMS power represents the average power a device can handle regularly without affecting sound quality or experiencing any distortion. So, you can think of RMS power as a reliable measure of a device’s ability to handle power.


In conclusion, RMS power is a crucial specification to consider when choosing speakers, as it represents the amount of power a speaker can handle continuously without distortion. Unlike peak power ratings, RMS power reflects the speaker’s real capacity to handle power and ensures that the speaker will not compromise sound quality over time.

Therefore, understanding RMS power is essential in selecting the right speaker for your needs, as it directly affects the performance and longevity of the device.

We hope you will be well aware about what is rms what does rms power rating mean in speakers, after reading this comprehensive guide. If you have any questions, feel free to comment  below!