You’ve probably come across the phrase “flat response” when researching headphones, speakers, or some other type of audio device. But what does it mean?
In this post, we’ll discuss what flat response means and how it can be helpful for music production.
What is flat frequency response?
In audio, a flat response means that the output frequencies are the same as the input frequencies. If an audio device has a flat response, that means it accurately recreates the sound without cutting out or boosting any frequencies.
In other words, what goes in is what comes out.
This is ideal in most studio situations since it gives a more “honest” impression of the audio signal. If a mix sounds good in a flat-response system, it should translate well to most consumer-level audio products.
If you were to look at a flat response on a frequency response chart, it would look like a flat line (hence the name).
Understanding Frequency Response
To really understand what a flat response means, you need to understand what frequency response is and how it’s measured.
Frequency response is how a device responds to the audio signal passing through it. It’s measured as the frequency range vs amplitude. If you’ve ever messed with EQ settings in your DAW or on your amp, you’ve changed the frequency response of that audio signal.
Human hearing ranges between 20 Hz and 20 kHz. You can generally break this range up into bass, middle, and treble.
Some devices will respond differently to different frequencies. For example, one pair of headphones might boost the bass, while others don’t. Neither one is bad. They’re just different.
Is a flat frequency response good?
That depends on the audio device and what situation you’re using it for.
When it comes to mixing audio for music, film, or podcasts, you’ll want to use speakers or headphones with a flat frequency response. This way, you’ll hear an accurate representation of the mix without any artificial boosting or cutting.
But microphones are a different story. Audio engineers might pick a microphone specifically for its frequency response. In some cases, a flat response mic might be the worst choice for the job.
Some microphones are engineered for a specific purpose. For example:
- The Shure Beta 52A is made specifically for capturing kick drums
- Mics like the Shure SM58 roll off the bass end to combat the proximity effect, making them ideal for capturing live vocals.
In each of these cases, a microphone with a flat response would muddy up the sound and be harder to mix.
How to find the frequency response of an audio device
Most gear manufacturers or retailers will specifically mention the frequency response in their promotional materials. Oftentimes, it’s listed as a range like “50 Hz-15 kHz”.
In some cases, you can find a frequency response chart for that device to help you figure it out.
What is the best frequency response for headphones?
If you’re mixing audio for music, podcasts, or even video productions, you’ll want to go with a good pair of flat response headphones. They’ll give you the best overall impression of how your mix sounds. And if it sounds good on a “flat” pair of headphones, it’ll sound good on just about any other headphones or speakers.
That being said, frequency response is entirely subjective when it comes to casual and recreational listening. It’s like a cup of coffee.
Some people like their coffee with heavy cream and sugar. Others like it black. Neither one is necessarily worse than the other.
Same goes for headphones. Some audiophiles love the nuance and clarity they get from a pair of flat response headphones. Others might prefer the extra rumble and enhanced bass they get from their Beats Studio3 headphones.
Again, neither one is objectively better than the other. It all just depends on your personal preferences.