JC-TYPE C Pro adopts the global top & sharp Realtek (Taiwan Realtek) single-chip integration solution, supports automatic identification of OMTP (national standard) / CTIA (American standard) headphones, and can support any external headphones 3 or 4 buttons (3 buttons are ordinary The standard 4 button is a new standard added by Google, and the 4th button is a Voice input button), SNR100dB, THD + N-90dB, supports up to 384K / 32bits sampling rate, you can debug EQ yourself, and the built-in Flash program is updated at any time. Adopt G-type earphone circuit, the frequency response supports 80kHz, 0 ~ 20kHz approximates a straight line, and there is only -0.06dB attenuation at 20kHz, and -3dB attenuation at 80kHz.