Understanding Frequency Response
A lot of people don’t know what frequency response is and why it’s important. Frequency response is a measure of the range of bass, midrange, and treble that your speakers can reproduce with clarity. The wider the frequency range, the more dynamic sound you’ll hear from your music or video game! This blog post will teach you how to understand frequency response so you can make an informed decision when buying new speakers or headphones.
Frequency Response Quick Guide
Don’t have time to read the whole article? Just want a quick rundown of what you should know about frequency response in speakers/headphones? Here’s a quick overview:
- Frequency response refers to the range of bass, mids, and treble.
- When a product features a range of 20 to 20,000 Hz, the first number represents the bass end of the spectrum while the second number represents the treble end.
- Since the average human can only hear between 20 to 20,000 Hz, this is the standard range for most speakers and headphones.
- Even though you may not hear bass frequencies below 20Hz, you’ll still feel them.
- A wider frequency response range does not always mean better sound quality
- There is a standard deviation that can be found in some ratings (±2 dB). This is called frequency tolerance and it indicates how different the sound is from a “flat” or neutral response. A lower number is better than a higher one.
- Two speakers can have the same frequency response but sound completely different. Frequency response on its own should not be a deciding factor when buying speakers or headphones.
Understanding Hertz
You’ll notice the frequency response that it’s measured in Hertz (Hz) and Kilohertz (kHz). If you’re wondering what that even is, it’s frequency. Frequency is vibrations per second and frequency response involves measuring these vibrations in a certain area.
Frequency Response Ranges
| Sub-Bass | 20Hz to 60Hz |
| Bass | 60Hz to 250Hz |
| Low Mid-Range | 250Hz to 500Hz |
| Mid-Range | 500Hz to 2kHz |
| Upper Mid-Range | 2kHz to 4kHz |
| Presence | 4kHz to 6kHz |
| Brilliance | 6kHz to 20kHz |
Sub-Bass Frequencies
The sub-bass frequency is 20 Hz to 60Hz. This low sound can be felt as well as heard, and it’s often the most powerful force at concerts or clubs. These lows are difficult for speakers to produce at a high volume without a dedicated subwoofer.
Bass Frequencies
Bass frequencies are mostly in the 60 Hz to 250 Hz frequency range. This is where your bass guitar, bass synths, and kick drums are seated. In cheaper audio equipment, manufacturers will often boost the bass somewhere between 60-250Hz to give products more bass. However, this can cause speakers to lose their low-end punch and definition (sometimes referred to as “woolly”). It can also affect the quality of the rest of the frequencies, particularly the mid-range, which can become difficult to hear (sometimes referred to as “muddy”).
Low Mid Range Frequencies
The low mid-range frequencies, also referred to as just the “low mids” fill the 250 Hz to 500 Hz range. This is where you’ll find the warm characteristics of vocals and instruments. This frequency range is the most affected by bass-boosting, which is often done in bass-heavy speakers or headphones.
Mid Range Frequencies
The mid-range frequencies are found in the 500 Hz to 2 kHz range. The mid-range, also referred to as “the mids” are very important for audio equipment. This is where a large chunk of the vocals sit, so it’s crucial that this range sounds good.
When the mid-range of a product is described as “upfront” or “present”, this indicates that the product offers a well-balanced frequency range and you’ll hear vocals and instruments clearly. If a product is described as having a “boxy sound”, this indicates that the mid-range is lacking.
Upper Mid-Range Frequencies
The upper mid-range frequency covers the 2 kHz to 4 kHz range. This range is where you’ll hear details such as sibilance in vocals and cymbal crashes.
This frequency range is very sensitive to frequency boosting, so if you’re listening to songs with a lot of frequency components in vocals and instruments, it’s likely that they will be boosted here when using low-quality equipment. This can cause audio fatigue over time since this frequency range is one of the most prominent frequency ranges for humans.
Presence
The presence range is an extension to the upper mids. Extending the upper mids creates a crisper, more vibrant sound. This is because 4 kHz to 6 kHz adds sibilance and intelligibility which allows us to hear all of those little nuances in your favorite song such as reverb tails or vocal effects.
Brilliance
Brilliance occurs in the range of 6 kHz to 20 kHz and refers to how the sound is perceived by the ears. Without brilliance, the audio sounds dull and lifeless.
Reading a Frequency Response Graph
A frequency response graph curve typically shows the frequency response of a speaker system. The primary reason for this curve is to show how well the speakers will reproduce sound across different frequencies, which relates to distortion in music and dialogue during playback on TV or movies. Frequency response graphs deal with the sub-bass, bass, low mids, and mid-range frequencies. Additionally, they also show mids and high mid-range, presence, and brilliance.
The graph above depicts two speakers. Speaker 1 has a frequency response of 20Hz – 20kHz, while speaker 2 also has a 20Hz – 20kHz frequency response. As you can see, they both look completely different on a graph and in reality, they will sound completely different too! The first will sound terrible with its lack of bass whereas the other would be ear piercing for such an intense spike at 1 kHz.
Of course, the values on the graph have been exaggerated in order to illustrate the point that a frequency response value on its own doesn’t tell you anything unless you see its graph or physically listen to the speaker.
Frequently Asked Questions (FAQ)
What is Frequency Response (FR)?
Frequency response is the measure of how a speaker system responds to different frequencies. It’s measured in hertz (Hz). Typically, a frequency response will be plotted on an X-axis and decibels on a Y-axis.
How does frequency response affect the sound quality of my speakers or headphones?
The frequency response of your speakers or headphones affects the sound quality because it determines how much, and in what way, the sound is amplified at different frequencies. If you have a frequency range that’s too narrow then an instrument or voice might be hard to hear if it falls within this range (especially for low-range instruments like drums). Likewise, if you have a frequency range that’s too broad then the sound may be distorted. Having a frequency response that’s as flat as possible is ideal.
What is a good frequency response for speakers?
Good frequency response for speakers: frequency ranges from 20Hz-20kHz and the frequency tolerance should be within ±3dB for each of these ranges.
Conclusion
I hope this guide helped you to understand what frequency response is, and how it affects how music sounds. The important takeaway should be that the frequency response of a product requires context. Simply stating “20 Hz to 20 kHz” is not very helpful in understanding what the product really sounds like, as two products with the same frequency response can sound totally different.
For this reason, the frequency response of a product alone should not affect your buying decision, unless you’ve either physically used the product to hear how it performs or viewed its frequency response graph. Most manufacturers don’t supply graphs for their products, which is what makes reviews so valuable. If another person has tested a product for you, you’ll get a better understanding of its performance.
