Choosing the right headset: technical characteristics

Frequency response

Frequency response is the technical element that influences how sound is distinguished by our ears. Displayed in Hertz (Hz), it ranges from 20Hz to 20,000Hz, from the lowest note to the highest note.

To understand it, take your favorite song: the bass is the drums, the mids are the singer's voice, and the treble is the cymbals. So, the wider the frequency range, the more precise and balanced the recreation made by the headphones.

The different types of frequency response:

Flat: All frequencies are reproduced equally, the sound broadcast is then “raw”, without coloration.

In "V": The bass and treble are accentuated, the midrange rather withdrawn, the audio is therefore more dynamic and punchier.

Emphasized bass: Low frequencies are emphasized, providing a punchier listening experience.

Highs Enhanced: Highs are emphasized, making high-frequency vocals and instruments clearer and more detailed.

Impedance

This is an element that directly influences sound quality: impedance! Expressed in ohms (Ω), it refers to the resistance of a headset to the alternating electric current that passes through it. The higher it is, the more difficult it is for the current to pass.

Imagine crossing a street: it is more difficult to do so if it is busy (high impedance) than if it is deserted (low impedance).

Low impedance vs. high impedance:

Bass: A headset is said to be a low impedance if it does not exceed 50Ω. Most consumer models are low impedance, simply because they provide a satisfactory volume on mobile devices, and without external amplification!

High: Any headphone with a rating of more than 75Ω is considered a high impedance. This type of headphone is not designed to be used with a mobile device without an external amplifier. It is preferred by sound professionals using high-end audio systems.

Sensitivity

Measured in decibels (dB) and expressed per 1 milliwatt (mW) of power, sensitivity has a direct impact on volume and efficiency! It corresponds to the volume level produced by the device at a certain power.

So, a 110dB headset will require less energy than a 90dB model to reach the same sound level.

Sensitivity and impedance: the dynamic duo

A headphone with high sensitivity and low impedance will easily drive any device, while a model with high impedance and low sensitivity will need an amplifier to perform at its best.

In practice, it's like going up a hill on a bike: it's easier with a light bike than with a heavier model!

Noise reduction

Noise reduction is an essential feature for communicating peacefully at work! In an open-office or on the move, it prevents any ambient noise from disrupting your listening experience.

Here are some elements to help you understand it in detail: Passive and active noise reduction: our decryption

So, passive or active?

Passive: This is the natural method! It uses the materials of the headset (like the ear cushions) to block outside noise.
Advantage: No electronic complications, it works constantly, even when the headset is turned off.

Active (ANC): It uses microphones and electronic circuits to capture noise and generate an opposing sound that magically cancels it out.
Avantage: Extremely effective against low-frequency noise, perfect for open-plan offices or commutes.

Harmonic distortion

To understand harmonic distortion without getting too technical, imagine you're playing the piano and suddenly every note is tagged by a ghost note... Well, that's what harmonic distortion is: it's the presence of unwanted sounds added to the original audio signal.

Distortions, where do they come from?

Headphone components: Diaphragms, magnets and other components may introduce imperfections.

Volume: The higher the volume you turn up, the more distortion can increase.