What are the performance characteristics of headphones and earplugs and how to detect them?

Performance characteristics

Headphones and earplugs are also a kind of electric sound conversion device, its structure is similar to the electric loudspeaker, but also by the magnet, the voice coil and the vibration diaphragm and so on. But the earphones and earplugs are mostly fixed. Earphones and earplugs can be divided into single channel and double channel. Most of the earphones are low impedance types, such as 20 ohm x2，and 30 ohm X2, commonly used as flat film moving coil. Earplugs have two kinds of high resistance and low resistance. The high resistance is 800 ohm,1000 or500 ohms, low resistance is 8 ohms, 10 ohms or 16 ohms.

Detect earphones and earplugs

 ( 1 ) Detection of the two channel headphones in the three extraction points of the two-channel headphone plug, the contact points of the rear end of the general plug are public points, the front end is the left and right channel extraction end, respectively. When detecting, the multimeter is connected to the public point of the earphone plug, and the other two extraction points of the earphone plug are respectively touched by the other one, the corresponding left or right channel should be issued with a " click " sound, the pointer should be deflected, indicating the value is about 20ohm or 30ohm, and the headphone resistance of the left and right channels should be symmetrical. If the measurement is silent, the pointer also does not deflect, indicating that the corresponding headphones have lead fracture or internal solder joint desoldering failure. If the pointer is placed near the zero position, it is indicated that there is a short circuit between the inner lead of the earphone or the plug of the earphone. If the pointer indicates that the resistance is normal, but the sound is very light, which is generally caused by the gap between the headphone diaphragm and the magnet.

( 2 ) Detect the earplug to fix any of the stylus on one end of the ear plug, and use another pen to touch the other end of the earplug plug, the pointer should be deflected, indicating that the value should be about 800ohm high resistance, low resistance 8 to 10ohm, and the earplug should be issued " click " sound, if silent, the pointer also does not deflect, indicating that the earplug leads are broken or the inner weld line of the earplug is unwelded; if the earplug is silent, the pointer indicates near zero, indicating that there is a short circuit fault at the inner lead of the earplug or the plug of the earplug.

This article is from Allicdata Electronics Limited.