Dec 07, 2021 07:00:00

An acoustic expert explains 'how to choose excellent headphones and earphones'

The evolution of earphones and headphones is tremendous, and there are a wide variety of products, so many people may not know what to choose. For such people, Timothy Sue, a music technology professor who studies acoustics, explains 'How to choose excellent headphones and earphones'.

Great headphones blend physics, anatomy and psychology – but what you like to listen to is also important for choosing the right pair
https://theconversation.com/great-headphones-blend-physics-anatomy-and-psychology-but-what-you-like-to-listen-to-is-also-important-for-choosing-the-right- pair-171171

According to Sue, choosing the right headphones requires thinking about the scientific, artistic, and subjective aspects of sound. First of all, on the scientific side, physically sound is made up of a series of vibrations of air consisting of a 'low pressure zone' and a 'high pressure zone'. Vibration is a 'sound wave cycle', and the sound, pitch, and frequency are determined by how many times this cycle occurs per second. Often referred to as '500 Hz sound', this means that high and low voltage cycles occur 500 times per second. The loudness, or amplitude, of the sound is determined by the maximum pressure of the sound wave, and the higher the pressure, the louder the sound. Based on these assumptions, headphones and earphones transform electrical acoustic signals into a cycle of high-voltage and low-voltage vibrations that the human ear can interpret as 'sound.'

When the sound enters the ear, the eardrum first converts the vibration of the air into mechanical vibration in the middle ear. Then, the inner ear filled with liquid turns into a fluid signal, which is finally transmitted to the brain as an electrical signal by nerves. Humans can hear pitches in the range of approximately 20 to 20,000 hertz, while human hearing does not respond equally well at all frequencies.

For example, when 'low frequency low sound' and 'high frequency high sound' exist in the same volume, one feels that the low frequency sound is quieter. It is also said that due to evolutionary factors, humans are most responsive to medium frequency sounds. Headphone and earphone engineers need to consider such a 'gap between physics characteristics and human perception.'

Headphones are small speakers that basically work as 'converting electrical signals into air signals,' which is the opposite of the ears. Most speakers, fixed magnet, wire coil, pushing the air moving back and forth around the magnet

diaphragm consists of four components: the suspension to keep the diaphragm. When the electric signal of music passes through the wire, the current changes and the magnet moves, and the magnet moves the diaphragm to compress and push out the air, producing treble, bass and pulses. This is the true nature of the 'music' that people hear.

At this time, depending on the material and size of the magnet or diaphragm, the electric signal may not be converted into an air signal. These can distort the sound and make some frequencies louder or smaller than they should be, Sue said. It is not possible to completely convert two different signals, but expensive headphones and earphones adjust the signal conversion in various ways.

In addition, age, experience, culture, music preferences, etc. affect 'preferences for frequency adjustment methods'. If you like hip-hop, you should appreciate headphones that emphasize bass, and if you like classical music, you should prefer headphones that do not have 'sound distortion'. Since good headphones are related to the elements of 'headphone design science,' 'content artistry,' and 'human experience,' Sue advised 'find headphones that pair with your favorite song.' ..