dB in Subwoofers: What is it? (Explained)

Subwoofers are designed to output the low frequencies and when it comes to dB it’s a straight calculation, i.e., the lower you set the frequency level the deeper will be the bass level.

However, setting up the right dB level will help to output the set frequencies as per your preferences and the type of sound.

Decibels or ‘dB’ is the unit to measure the sensitivity of the sound or the intensity of the sound waves.

Similarly, in the world of audio dB is used to measure the loudness of the subwoofer, speaker, and similar sound systems.

The dB SPL can vary depending on the type of music, set frequencies, and the type of sound system (such as subwoofers and speakers).

Let us understand the concept of setting dB SPL in a subwoofer system.

Key Takeaways

  • Speakers and subs come in different shapes and sizes, some may work together and others may need special settings.
  • The sensitivity of sound is the SPL (Sound Pressure Level) typically measured in decibels (dB).
  • Subwoofers and Speakers may not always use the same amount of dB SPL setting to play different types of music together.
  • To ensure a balanced output in a music or audio you will need to set the right dB SPL in your subwoofer and speaker.

What is dB in Subwoofers?

The term dB or decibels has nothing to do with subwoofers alone, in fact, it is applicable wherever there’s the presence of sound waves.

Similarly, ‘dB’ (decibels) is the unit to measure the sound levels in a subwoofer, speaker, and other audio systems.

What is the best dB for subwoofers?

For subwoofers, the best dB SPL setting is anywhere between 65 to 85dB.

However, the lower range which is 70 to 75dB would be fair enough for a living room.

The higher range is typically used for concerts and in movie theaters to output specific sound effects.

Finally, setting up the dB level also depends on the size, type, and specifications of the music system.

What dB should I set on my Subwoofer?

Increasing the sound level of a subwoofer will cause distortion, similarly, a complete decrease in sound level will result in no output.

To match the right SPL setting of your subwoofer start by setting it to 70 or 75dB.

You can then decrease or increase the setting to adjust and reach the desired sound level and frequency.

This can be done when you want to adjust the dB SPL for different types of audio and music.

How do you set dB SPL for mid-highs and mid-lows?

Setting up the dB SPL along with Mid-lows and Mid-highs are typically applicable for rock musical tones. 

To manually adjust these settings you will need to be a pro and set it with the help of an equalizer.

Or, otherwise, you need to have a setup that automatically adjusts these settings for you. 

However, most music lovers have their own preferences for the way they want to listen to their favorite musical notes. Hence, to customize the frequencies and sound levels accordingly Equalizers come into the picture.

Equalizers are electronic devices that can control the way frequencies and sound levels of different ranges are released from a set of audio systems.

Rock music typically includes electric guitars at high-mids and rock drums at low-mids settings.

Also, to output the best tones, a precise db SPL setting needs to be applied for different frequencies such as mid-lows and mid-highs.

Let us look at the image and its explanation below to understand the best setting to play a rock musical tone.

Equalizer setting for mid lows and mid highs

To set up Rock music as a genre is among the most challenging settings to be applied to an Equalizer.

This is because the sound of electrical guitar strokes typically sits in the high-mids. On the other hand, the deep vocals and the rock drums lean towards the low-mids.

If you look at the image above the db SPL settings for the lowest and highest frequencies are on the higher side.

The dB SPL setting from the lower and higher frequencies is set in a slanting position towards the mid-range.

The mid-range is at the lowest dB SPL if you refer to the image above; the dB SPL setting is set below 0 at the 1kHz frequency range.

There’s a slight increase in the dB SPL for frequencies lower and higher than 1kHz.

This is the usual setting on an Equalizer for rock musical tones that require frequencies such as mid-highs and mid-lows.

Additionally, most professional Rock guitarists refer to the classical ‘Rock Curve’.

This particular setting forms a proper curve on an Equalizer while setting up the best mid-highs and mid-low settings.

The above setting will suit you if you want to create rock music and it will differ for different genres.

How does the sound system measure the subwoofer’s dB?

Most sound systems have an automatic speaker/room correction system.

Typically a microphone is provided to be plugged into the front of the receiver.

Test tones are sent out to all the connected speakers and subwoofers which are picked by the microphone.

The tones are then sent back to the receiver which further determines the number of connected speakers.

Additionally, the size of each speaker and the distance of each speaker from the listening position is also recognized by the receiver.

Using that data, the receiver determines the best crossover point between the speakers and subwoofers, including the ideal sound level relationship between the two.

Can you manually determine a subwoofer’s dB level?

To measure the dB SPL of a subwoofer, speaker, or other sound systems you can use a portable sound meter. It is also known as an SPL meter and is a handy device for your sound system that does not have an automatic correction system.

Additionally, there are a lot of sound meter (SPL meter) apps that can be installed on smartphones. These apps work with the microphone of your phone to determine the sound levels.

Final Thoughts

The unit used to measure the intensity or the sensitivity of sound waves is measured in dB.

When it comes to subwoofer or speaker, the higher you set dB SPL for a set range of frequency the louder you’ll hear that effect.

Audio systems have now advanced and include a built-in auto-correction technique when it comes to adjusting sound levels with dB SPL.

Most professionals add Equalizers to their sound system to match the frequencies with sound levels.

Armed with a Diploma in electrical engineering and a remarkable 12 years of expertise, he excels in rejuvenating music systems, washing machines, dryers, and laundry-related appliances. Manish's profound insights and practical know-how establish him as a credible authority in appliance and music system repairs. Contact: manish.singh (at) subwooferblog.com. He's always ready to lend a helping hand!