Bass boost is a great way to enhance the low-end frequencies of music or other forms of audio. Making the bass more prominent is required if you’re playing music in large spaces.
Can bass boost damage subwoofers and speakers?
As a general rule, speakers and subwoofers should be able to withstand bass boost. The only time that there is a risk of damage is if the SPL is extremely high. At exceedingly high volumes, boosting the bass could cause damage.
To avoid damaging subwoofers and speakers, it’s important to stick to volumes that aren’t ridiculously loud.
Depending on the size of the speaker cone and subwoofer, and their build quality, they will be capable of handling varying sound pressure levels.
Bass boost shouldn’t pose any issues if the volume is kept to a sensible level. In this guide, I’ll highlight the potential dangers of bass boost and how to minimize the risk of damage.
Bass Boost, Subwoofers & Speakers
So, what is Bass Boost?
Bass boost is the process of enhancing the low frequencies in a recording.
Some mixers, speakers, amps, or interfaces have dedicated buttons or switches which instantly add more bass to the output. In other cases, bass boost might be achieved through equalization.
- Regardless of how the bass is boosted, it is done to achieve one result – more power in the low end.
This is especially effective if the audio system contains a subwoofer, which is a specialized speaker designed to reproduce low-end frequencies. It is usually paired with a tweeter, which is responsible for the high-mid and treble output.
If you’ve ever used an equalizer before, you’ll be familiar with the basic concept of bass boosting. Stereos in vehicles commonly have built-in EQ controls, which allow you to choose a preset or add or remove the bass, mid and treble frequency bands.
In the same way, the bass boost feature is a quick and easy solution to a mix that is lacking some low-end power.
Perhaps you’re listening to music in a large room, or you need to crank up the bass for a party. Whatever the reason, bass boost is a very useful and efficient way to achieve this.
Nevertheless, increasing the volume of low-end frequencies doesn’t come without a degree of risk.
Bass frequencies force the speaker or subwoofer to work harder, that’s why you can feel the bass when you stand next to a speaker that is playing at high volume. I wouldn’t recommend doing that if you haven’t experienced it!
Several factors come into play when you bass-boost the audio which could potentially lead to your equipment being damaged. These are:
- Frequency response
- Max SPL (Sound Pressure Limit)
- Speaker/subwoofer size
It’s very unlikely that bass boost will cause damage to your subwoofer or speaker if you’re listening to reasonable levels. However, I’m aware that sometimes, it’s necessary to crank the volume. If you need to do this, there are some measures you can take to minimize the risk of damage.
Low-Frequency Volumes & Speaker Specs
It’s common knowledge that high frequencies played at loud volumes are more likely to damage your hearing. However, the reverse is true when it comes to speakers and subwoofers. Low-end frequencies are much more likely to break these devices.
The simple reason for this is related to physics.
All sounds are on the frequency spectrum, which is measured in Hz. The human ear can generally hear between 20Hz – 20kHz. Nevertheless, some music and audio contain sub-bass frequencies that potentially drop below the 20Hz threshold.
Although these frequencies cannot be heard by the human ear, their presence is felt. Sub-bass frequencies add a thick layer to the bass which makes it sound fuller, providing the subwoofer is capable of reproducing those low frequencies.
What Happens When Bass Boost Is Activated?
When the bass boost is activated, the bass driver in the speaker needs more air to push the audio waveform. This allows the waveform to propagate and form so that it can be heard by the listener.
The more air the driver is pushing out, the more the speaker cone moves. If the speaker cone is forced to flex too aggressively, it can break. That’s the most common cause of someone “blowing” their speaker.
So it’s not solely the bass boost that causes the speaker or subwoofer to be damaged, but rather the combination of the bass boost with excessively high volumes.
That brings us to a specification that is used to measure the maximum volumes of speakers – SPL.
Check out this video on the incredible JTR Captivator RS2 Subwoofer.
What Is Subwoofer SPL?
SPL is short for sound pressure level.
It’s measured in decibels, and you can find it on the specs of any speaker or subwoofer. To put it simply, SPL measures how loud something is, concerning the positioning of the listener and the environment.
If engaging the bass boost causes the speaker to exceed, or come close to its maximum SPL, this is likely to cause damage. Therefore, establishing the SPL of the device is essential if you want to avoid breaking it.
You can measure SPL by using a device called a “Decibel Meter”, or a “Sound Pressure Level Meter”. The sound is projected into a small microphone, and the meter then evaluates the sound pressure and converts it into decibels so that you can gauge how loud the volume is.
The table below illustrates the audio frequency spectrum.
|Frequency (Hz)||Audio Band|
|10k-20k||Upper High End|
If you intend to use a bass boost and need relatively high volumes from your subwoofer and speaker, it’s advisable to check the max SPL beforehand and get yourself an SPL meter to ensure you don’t push the levels into dangerous territory.
Why Do Subwoofers Blow?
We’ve covered the fundamental reasons that a bass boost can cause damage to your audio system. Now, let’s look in more detail at the technical aspects that cause the subwoofer to “blow”.
When you give your subwoofer too much power, the extra volume is likely to cause distortion. Distortion occurs when the waveform becomes too loud and starts to clip. If you’re experienced in recording music, you’ll probably have encountered digital clipping before.
Clipping and saturation aren’t likely to cause damage to your subwoofer if they happen occasionally.
The device can handle a small amount of clipping, but if it happens over a prolonged period, it can potentially blow the subwoofer cone and cause irreparable damage.
This damage is caused by the physical movement of the subwoofer cone and voice coil. When the bass boost is engaged, these mechanisms are forced to flex more intensely. This additional movement is then exacerbated if the volume is also increased.
There’s a threshold point where the subwoofer is unable to play the bass frequencies cleanly, and the sound begins to distort. This is the point at which the speaker cone and the voice coil are at risk of damage because they’re working harder than they are designed to.
Clipped signals occur when the bass boost caused the volume of the low-end waveforms to exceed the electronic capability of the subwoofer’s inner circuitry.
This causes the waveforms to take on a square shape, with sharper peaks and troughs than the stereotypical sine wave. These sharp transients force the subwoofer cone to do things that it is perhaps not designed to do.
The first sign that bass boost is causing the audio to clip is likely to be a “pop” sound. This indicates that the signal has attempted to move the subwoofer speaker cone too quickly.
Another common sound you’re likely to hear through the speaker when the sound is clipping is a “sizzle”. This indicates that the signal is telling the cone to stay all the way forward, or back, which it is not designed to do.
The subwoofer or speaker cone needs to move freely and fluidly to reproduce the bass–boosted frequencies without causing any noise issues or potentially being damaged. This is why it’s so important to ensure that the volume isn’t overly high when you’re engaging the bass boost feature.
How do I know if my speaker is blown?
The most common aural sign that your speaker is blown is an undesirable scratching or buzzing noise that is produced when it is turned on. If the speaker is commonly ruined, it might not be able to play any sound at all.
Why do my speakers crackle when the volume is turned up?
Crackling is a sign that there is an interrupted electrical current within the speaker. To rectify this, check all of the cables that connect the speakers to the amp or source device, to determine which is causing the unwanted noise.
Does a capacitor boost bass?
Capacitors supply power to the amplifier of the subwoofer when it is required, so in theory, they can boost the presence of bass. They are also useful for ensuring that to subwoofer has adequate power at all times.
Can you use regular speaker wire for subwoofers?
Check out my article on this subject. You can read it here.