Frequency response is the range of bass, mids and treble at which the headphone drivers are capable of reproducing sound from the lowest tones to the highest. Lots of audiophiles ask us if we have headphones with the flattest sound signature. What they're describing is a balanced sound whose frequencies are evenly spread across the entire frequency range.
The average human ear can hear frequencies between 20 Hertz to 20,000 Hertz. While most basic headphones come with a frequency response of 20Hz-20kHz, there are headphones where the lower frequencies can be as low as 5 Hertz. We've also seen headphones with a higher frequency of 35,000 Hertz. You may think, how can a man possibly hear such a range! Extremely low and high frequencies might not be heard but they're definitely felt, enhancing the ultimate aural headphone experience.
FREQUENCY RESPONSE & MUSIC GENRES
Lower the frequency, more is the thump and bass whereas higher the frequency, you will hear more shrill and sharp sounds. A scientific approach to picking out new headphones should depend on the choice of music genres. For Bollywood, EDM, pop, reggae, techno, and dance hall genres: low frequencies are preferred. Higher frequencies allows one to experience each and every beat of a classic rock metal song. Someone who enjoys Mozart, Bach or other classical music artists would appreciate the music to be left uncoloured.
While a headphone with a wide frequency range won’t necessarily have great sound quality, lots of musical detail can be unraveled with such headphones. A song is usually composed using innumerable instruments to fill up the musical paraphernalia. For example, an AR Rahman track would have a tabla to fill up the sub bass, S. P. Balasubramanyam singing a raag tunefully and bringing out the lower mids, Lata Mangeshkar shining on the upper mids with her melodious voice and finally a clarinet brightening the treble. Further, with the right music listening setup, one would hear things that would randomly give you goosebumps. These sounds are spread across the wide sound spectrum, which you will hear only if your headphones frequency specs allow it, and if you've got the right headphones of course!
FREQUENCY RESPONSE GRAPHS
It's not a very easy task to measure the frequency response of a headphone. How you can accomplish this, is by positioning a very sensitive mic to record sound at every single frequency. This mic would be placed right between the headphones in the place of a head. Then you can effectively measure how the headphone reacts to every sound and put it on a graph.
"I've been trying to make good headphone measurements for about twenty years now. I've given this subject a lot of thought, and the answer has always seemed simple and obvious to me."- Tyll Hertsens, InnerFidelity (Founder of Head Room and credited with Inventing the Portable Headphone Amplifier)