Earphone By Richsound Electronic Co., Ltd.

Following are the technical specifications of Earphone:
Transducer : Moving coil dynamic speaker
Resistance :16 IC A 10%
Rated Impedance: 17 IC A 15% (Rated Power @ 1 KHz)
Sound Pressure Level (SPL):100 A 3 dB SPL at 1 KHz 1mWi 0dB=20uPa=0.0002uBari by Artificial EAR IEC318
Resonance Freq (F0) : 220 Hz A 20 % at 1mW, free field.
Frequency response : F0 to 20 KHz
Refer to tolerance window below (position typically on IEC 711 Ear)
Different between L & RWithin 3dB at 1 KHz
THD<2% @ 1KHz, -15dBVrms, <5% @ 1KHz, -6dBVrms
(position typically on IEC 318 Ear)
Rated input power (20 Hz to 20 KHz) 3 mW
Maximum input power : 5 mW
Polarity : Left / Right side may not be interchanged. With a mono signal applied, both phono-elements shall be in phase.
Buzz and Rattles : Shall be normal input power 0.2 V sine wave (100 Hz to 2 KHz)
Connector stability : When plug is turned in socket; no crackle is allowed.