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If you listen to music with a mobile phone or portable player, try to choose a headset with low impedance and high sensitivity. Usually, Earphones with an impedance of 16 or 32 ohms can be driven well.
2. Frequency corresponding range. It refers to the frequency range that the headset can express. The general value is 20-20000 Hz (bass treble). 12-39000 Hz means that the headset can express more audio details, and the sound is "more real". 30-17000 Hz means that the headset can not distinguish the details of the audio segment below 30 Hz, but the bass effect is "heavy" and has weight. The treble situation is similar.
At the same volume, the smaller the difference between loudness as low as 20Hz and loudness as 1kHz, the better the earphone diving or floating. Many high-end headphones, such as hifiman's Shangri La, have a frequency response range of 7 ~ 120kHz, but the frequency error is very small within the range that human ears can hear. Therefore, the frequency error range is also a parameter that needs special attention.
3. Unit sensitivity. Sensitivity refers to the sound pressure level that can be emitted when the headset inputs 1 MW power (taking 1kHz as the standard), that is, the volume. In general (with exceptions), the smaller the impedance, the higher the sensitivity. At the same time, the easier it is to drive the headset, the easier it is to make sound.
4. Total harmonic distortion: it indicates that the sound quality of the headset is stable, clear and fidelity. The indicator of "less than or equal to 0.1%" of the above headset is quite good. The general headset is about 0.7%, and the smaller the value, the better.
