The impedance of the earphone is the abbreviation of its AC impedance. The impedance refers to the impedance of the alternating current in a circuit with resistance, inductance and capacitance. The impedance is in ohms (Ω). In general, the smaller the impedance, the easier it is for the earphone to sound and the easier it is to drive.
The impedance of the earphone changes with the frequency of the audio signal it plays back. Generally, the impedance of the earphone is the highest at the low frequency, so the attenuation of the low frequency is greater than that of the high frequency; for most headphones, increasing the output impedance makes the sound Darker and more mixed (the amplifier will also weaken the control of the headphone drive unit), but some headphones need to be better at high impedance. If the headphone sound is sharp and harsh, consider increasing the effective output impedance of the headphone jack; if the headphone sound is dull and turbid, and is driven by a power amplifier, consider reducing the effective output resistance.
Headphones with different impedances are mainly used in different occasions. On desktops or amplifiers, VCDs, DVDs, TVs, etc., high-impedance headphones are commonly used. Some professional earphones have impedances of more than 200 ohms. This is for professional The headphone jack on the machine is matched. If you use a low-impedance earphone at this time, you must first turn down the volume and then plug in the earphone, then adjust the volume a little bit to prevent the headphone from being overloaded or the voice coil is deformed and misplaced. .
Impedance
Impedance does not refer to the resistance of the earphone itself. After impedance matching, the power allocated by the earphone can be increased. The smaller the self-resistance, the easier the headphone is to drive; the larger the self-resistance, the harder it is to drive. The average Walkman headphones have an impedance of 16Ω-64Ω. Generally, the headphone impedance is the highest at low frequencies, and the attenuation at low frequencies is greater than that at high frequencies. For most headphones, increasing the output impedance will make the sound darker and more confusing (the power amplifier will also weaken the headphone drive unit), but some headphones need to be better at high impedance. The impedance of the headphones is too loud, but for a variety of portable Walkmans, such as CD, MD or MP3, low-impedance headphones (usually less than 50 ohms) are generally used, because these low-impedance headphones are easier. Drive, while paying attention to high sensitivity, on the Walkman, MP3, MP4, CD, sensitivity indicators are more important. Of course, within a certain limit, a high-impedance earphone is better with a sound source with a large output power.
The size of the headphone impedance is also closely related to the sound quality of the headphone. The impedance varies with frequency. The impedance of the headphone is small at low frequencies and large at high frequencies, so for most headphones, increasing the impedance will make the sound Become darker.