Are you looking for good headphones? When you start comparing specs, you will likely come across many technical terms.
Among these is frequency response, which is the range of bass, mids, and treble measured in Hertz (Hz).
Different models have varying specs, but typically, the best frequency response for headphones is within the range of 20 Hz and 20,000 Hz.
To give you a better understanding of this, this guide will dig deeper into frequency response, why it matters, and how it’s measured.
Understanding Frequency Response
Headphones work by converting electrical signals into audio signals, which is the actual sound we hear from the device.
However, during the conversion process, the reproduction of certain frequencies may vary slightly.
It’s either the headphones boost or de-emphasize some frequencies, altering the intended sound in the process.
This is where frequency response comes in.
In a nutshell, it refers to the range of frequencies that headphones are capable of producing.
Also, frequency response describes how accurately your headphones reproduce each frequency of your audio content.
Why It Matters
Your starting point to finding the best headphones is learning about frequency response. There’s just no getting around this.
Whether you’re looking into understanding how speakers and headphones work, the concept of bass management, and everything about audio, you have to learn about frequency response.
Do note that headphones and other audio devices have to be as close to the perfect frequency response, or they won’t sound right. It’s as simple as that.
To fully understand how frequency response works and why it matters, you need to learn a little about the physics of sound.
As you may already know, sound travels in waves.
The distance between the crests or top points of a wave and the next is called the wavelength.
Waves with higher frequencies have crests closer to each other and so have shorter wavelengths.
On the other hand, waves with lower frequencies come further apart, which means they have longer wavelengths.
Headphones and speakers convert electrical signals into sound through vibrations.
The vibrations then create the sound waves that we hear from our devices.
The vibrations that produce sound at 20 Hz are very low, almost like a bass rumble.
Here’s how it is supposed to sound or feel since bass frequencies are felt more so than heard.
Take note that the lower the Hz, the more bass you can get. Although, typically, bass frequencies range from 20 to 300 Hz.
That said, if you’re looking for headphones for listening to bass music, you should be looking at those with the lowest possible starting frequency response range.
On the other side of the spectrum is the treble.
It refers to sounds with a frequency or range at the higher end of human hearing and corresponds to “high tones.”
The generally accepted frequencies for treble are between 8,000 and 15,000 Hertz.
Best Frequency Response for Headphones
Frequency response relies on humans’ perception of sound.
People with perfect hearing can hear from approximately 20 Hz in the bass to about 20,000 Hz in the treble.
Therefore, the ideal frequency response for headphones should cover the audible sound range of 20 Hz to 20,000 Hz.
Some models have frequency responses that go lower and higher than this range.
Normally, the better range for your headphones, the wider the spectrum of audible sound they can produce.
However, unless your hearing is exceptionally good, it doesn’t really matter.
If you are 18 or above, you can’t probably hear over 18,000 Hz.
Meanwhile, those in the middle (40 to 60 years old) won’t be able to hear past 13,000 to 14,000 Hz.
Lastly, and needless to say, frequency response is worse for older people, as they can’t hear past 3 Hz.
What does this all mean for you?
Basically, if your ears can’t hear the lowest and highest audible frequencies, you won’t be able to tell the difference between a headphone with the standard frequency response and one with higher frequency response.
Comparing Frequency Responses of Headphones
Having a good frequency response is important for all headphones, regardless of their type or design.
It has the largest effect on the perceived sound quality of the audio device.
Therefore, choosing headphones with the ideal number will guarantee the best listening experience.
Fortunately, comparing headphones based on their frequency response is easy, as this indicator has a theoretical value.
However, unless the product specs include a dB tolerance alongside the value, the advertised frequency response doesn’t mean anything.
For example, a pair of headphones could have a frequency response of 16 Hz to 22K Hz.
By simply considering its face value, it’s easy to assume that these headphones sound great because they exceed the audible range of 20K Hz for the treble.
Unfortunately, there is no way to figure out if there is wide variability within this range.
Thus, a better and more helpful way of detailing this spec is by adding the tolerance value of the frequency, which is measured in dB.
For example, it should be written as 16 Hz-22K Hz ±3 dB.
Ideal Frequency Response Deviation
The dB rating tells us the maximum deviation (boost or cuts) in the frequency response range.
For most people, 3 dB is considered the lower limit of what you can hear.
This means that small deviations of 1 dB or 2 dB are very subtle and nothing to be concerned about.
Meanwhile, multiple variations of 3 dB or above suggest some perceivable alteration to the sound you hear from your headphones.
It suggests that the sound deviates farther from a neutral or “flat” response.
This can be particularly problematic for some users, especially those who use headphones for producing music.
That’s because a higher dB rating usually means that certain musical notes and tones will likely sound exaggerated or masked.
With all things considered, you want to look for headphones with good frequency response and lower deviation, not exceeding ±6 dB.
Unfortunately, very few manufacturers include the tolerance value in their specs.
This makes it difficult for many buyers to determine the best headphones for their audio needs.
How Headphone Frequency Response Is Measured
The way frequency response is measured in audio devices like headphones is quite complex.
This is probably why most frequency response ratings are provided by third parties rather than the manufacturers themselves.
These companies conduct frequency response tests on varying headphone brands and models.
These are then used by headphone reviewers and buyers when comparing products.
Unlike loudspeakers, headphones are not easy to measure and would often require the use of a dummy head.
This equipment simulates the human head and ears.
Frequency response measurements are then translated into graphs so that they are easily interpreted by reviewers or users.
Typically, a headphone with an excellent frequency response has a pretty “flat” curve.
Yes, we call it a curve because the frequency response will curve or roll off in the low bass and high treble, no matter how subtle the deviation is.
The absence of serious peaks, dips, or up-and-down variations suggests that the headphones produce accurate, almost neutral, or close to natural sound.
Do Infrasound and Ultrasound Frequencies Matter?
At this point, we can say that the best frequency response for headphones is 20 Hz to 2K Hz.
It is the only audible range that human ears can perceive, considering the listener has perfect hearing.
However, earlier, we mentioned that higher-end headphones tend to have frequency responses that extend well below or above this ideal range.
They are called infrasound and ultrasound frequencies.
An example is the Sony WH-CH710N, which has a frequency response of 7 Hz to 20K Hz.
Although the end bass frequency is inaudible to human ears, it can certainly be felt.
That said, they can significantly enhance your listening experience.
Additionally, headphones with larger frequency responses will generally be higher-quality than those with lower ranges.
The reason? To capture such wide frequencies, these devices need to have solid engineering and are typically made with better components.
However, do note that this range we’re talking about concerns the tone or pitch of the sound you hear from your headphones, not the volume.
That said, better frequency response does not always mean better sound quality.
The latter is affected by some other factors, such as the signal-to-noise ratio and distortion ratio, among others.
Understanding frequency response in headphones is your starting point to finding the best product for your audio needs.
To recap, here are some of the most important things you should know about it:
- 20 to 20,000 Hz is the standard for most headphones, as this is the generally accepted audible frequency range.
- Some headphones offer wider ranges, but it doesn’t always mean better sound quality. However, it could mean fewer distortions and a better listening experience.
In the end, it will be for the best if you look for headphones that include the tolerance value in their frequency response spec.
Basically, it determines how far the sound deviates from the “neutral” response.