If you are the frugal type of person, I’m sure this question pops up in your head every now and then. If you also enjoy music as I do, then I’m sure speakers are one of the home devices you use all the time. Most of us even leave them on and never consider turning them off.
However, is this bad habit skyrocketing our electricity bills? Do speakers use a lot of electricity?
Generally, speakers don’t use a lot of electricity. On average, speakers use 100 Watts of power, which isn’t much compared to many other electrical and electronic appliances we use. The amount of electricity a speaker uses depends on the loudness of the audio being played, the speaker amplifier’s volume, and the speaker’s sensitivity.
If this sounds too summarized for you, fret not. Because I’m going to explain in detail everything you need to know about speakers and electricity.
At the end of this article, you’ll learn about what accounts for the power consumption of speakers. This is essential because it really depends on the type of speakers you own and how you use them.
Later in the article, you’ll learn how to calculate a speaker’s power consumption so that you can know exactly how much electricity your speakers are consuming. If all of this sounds interesting, let’s jump right in!
What Accounts for Speaker’s Power Consumption?
A speaker doesn’t have a fixed amount of power it consumes when it is in use. Three main factors contribute to how much energy it consumes. I’m sure if you paid attention to the third paragraph of this article, you already have a clue. However, let’s dive a bit deeper into the three main things that account for how much electricity a speaker draws.
1. Loudness of Audio Signal
If you listen to a lot of music or any audio in general, you have realized that different audio has different loudness levels. For instance, if you have paid little attention, then you know pop music, in general, is much louder than jazz, or even country. That was just an example.
The point I want to make is, how loud audio is affects how much electricity is drawn by the speakers. I’m sure if you’ve read my post on how bass damages speakers, you already have an idea about this. However, let me explain.
For speakers to play any sound, it draws current from the amplifier it is connected to. This current causes the speaker cones to move back and forth to produce sound.
The amount of electricity that will be drawn by the speakers depends on how loud the audio signal is. Everything else being equal, for a quieter audio signal, a speaker will draw a much lower current, and for a loud audio signal, a speaker will draw a much higher current.
Essentially, the higher the current a speaker draws, the louder the sound it generates. This means it draws current based on the audio’s loudness level in order to replicate the audio’s dB level as close as possible.
If you don’t remember anything in high school, I’m sure you’ll remember this one — Electrical current is directly proportional to Power (P =I^2 x R). This means, the higher the current a speaker draws, the higher the power it consumes.
Volume has a direct impact on the power consumption of speakers. The more you turn up the volume on your amplifier, the more electricity the speaker consumes. Here is how it works.
When you turn up the volume on the amplifier, it feeds more power (or current) to the speakers. This causes the speaker cones to travel back and forth much further than before, which, in turn, makes the speaker play louder.
This means if you love cranking up the volume on your amp, just know your speakers will consume some extra watts in order to play loud. Essentially, the more power you feed to a speaker, the louder it plays.
3. Speaker Sensitivity
The speaker sensitivity is a crucial factor that depicts how much electricity a speaker will consume. For those who don’t know what speaker sensitivity is, I’ll briefly explain.
A speaker’s sensitivity rating refers to the number of decibels a speaker can produce per one watt of power at a distance of one meter. Sensitivity rating is usually found on the spec sheet of any speaker. You can also find them online on product pages of speakers.
For instance, if a speaker has a sensitivity of 60dB, it means at one watt of power supplied to it, it will play audio at 60dB loudness one meter away from the speakers. So if you are standing a meter away from the speaker’s, you’ll hear a 60dB loud audio.
However, if you want to increase the decibels by 3, you need to double the power. What do I mean by this? Let’s look at our example again.
If you want to increase 60dB to 63dB at a meter away from the speakers, you’ll have to supply the same speakers with 2 watts. To increase it from 63dB to 66dB, the speaker needs 4 watts. From 66dB to 69dB, it needs 8 watts of power, and so on. I hope you get the picture. So, as you can see, the power can add up to a big number pretty quickly.
Every speaker has a different sensitivity rating. And the power that will be consumed by the speakers will depend on how loud you want the speakers playing as well as the speaker’s sensitivity. Let me illustrate with an example.
Let’s say you have two different sets of speakers — Speaker A and Speaker B. Speaker A has a sensitivity rating of 74dB, and Speaker B has a sensitivity rating of 85dB. Let’s say we want to play these speakers at 95dB loud.
At 74dB sensitivity rating for Speaker A, it will require 128 Watts of power to drive them to play at 95dB. On the other hand, at 83dB sensitivity rating for Speaker B, it will require only 16 Watts of power to play them at 95dB.
That is a big difference in the power required to play two speakers at the same dB level. In essence, some speakers consume more power than others. The higher the sensitivity rating of a speaker, the lower the electricity it consumes.
So, when you are out there shopping for a speaker, you should pay close attention to the sensitivity rating if you are the frugal type of person.
How to Find How Much Power a Speaker Consumes
If you really care about how much electricity your speakers are consuming, then this section is for you. That’s because I’ll walk you through two ways to find how much power your speaker draws. Let’s not waste any more time and get into it.
1. Use Kill-A-Watt Meter
The simplest way to know exactly how much electricity your speakers are consuming is by using a Kill-a-Watt Meter.
For those who don’t know what it is, this is a portable metering device that measures exactly how much power a device is drawing. You can get it on Amazon for about 30 bucks. Let me show you how simple it is to use.
You first plug the Kill A Watt Meter in a socket outlet, and then you simply plug in your speaker or amplifier in the Kill-A-Watt Meter. And you are done.
The meter will begin to measure how much power the speakers are drawing. The meter will keep measuring the speaker’s power consumption for however long you leave it plugged in. And then it will automatically calculate the total amount of power consumed by the speaker while it was working. This will be calculated in kWh. It doesn’t get any easier than that.
Once you have the kWh reading from the Kill A Watt meter, you can simply multiply it with the Electricity cost per kWh to know exactly how much electricity bill you are paying for your speakers. According to Electric Choice, the average electricity cost per kWh in the United States is 13.19 cents.
One nice thing about the Kill A Watt Meter is you can use it to check the power consumption of any electrical or electronic device or appliances — from your TV, refrigerator, Air-Conditioner, or anything you can think of. If you really care about power consumption, you should definitely get one because it’s really handy.
2. Manually Calculate Speaker’s Power Consumption
This method will require some calculation on your end. And also, you may not get the exact power consumption of the speakers. However, you’ll get a rough idea of how much electricity it is using. Here is how to go about it.
- 1. Find the speaker’s power ratings. You can find this online on the speaker’s product page, the label on the speaker itself, or in the user manual.
- 2. Calculate on average how long you use the speakers in hours.
- 3. Multiply the speaker’s power ratings by the number of hours you use the speakers to find the kWh readings
For instance: Speaker’s Power Ratings = 150W
Average hours per use = 6 hours
Power used by speakers = 150W x 6h = 900Wh = 0.9kWh
Once you have the kWh readings, you can multiply it with the electricity cost per kWh to find how much electricity bill you are paying for your speakers. As I mentioned earlier, this method won’t give you the exact figures, but it will be close to the actual one.
Do Speakers Use Power When Not In Use?
Short answer, yes. Speakers use power when they are on but not in use. However, the power it draws is not much. Speakers draw more power when they are playing audio and even more when the volume is turned up.
Class A amplifiers, which were very popular back in the day, consumed a lot of power. They were not optimized to be energy efficient. These amps consume the same amount, whether they are in use or not. Because these amps consume power even not in use, they get hot very quickly. Class A amps are still made, but they are not as mainstream and popular.
Besides Class A amplifiers, all the other classes of speaker amplifiers are much more energy efficient. However, they will still draw some amount of power.
So my recommendation is, turn off your speakers when you are not using them if you really want to save on some electricity costs.
Speakers don’t consume much power compared to your other home appliances such as cooling and heating systems, or even your TV sets.
However, if you want to save some cents on your speaker’s electricity bill you should consider getting a speaker with a higher sensitivity rating. If you have read my post on how long speakers last, then you’ll know that over the long term, good speakers will save you some cash.
Also, turn them off when they are not in use. That’s because the speakers still draw power even when they are not playing.