headset:

a) Frequency response: 125Hz~8000 Hz,+17 dB (0dB=20uPa) (input power=1mW); b) Electrical impedance: 32Q+20%;

c) Characteristic sound pressure level (sensitivity): ≥ 100dB/1mW (0dB=20uPa).

Microphone:

a) Frequency response: 40-20000HZ

b) Type: Electret microphone;

c) Free field sensitivity: -47+2 dB (0 dB=1V/Pa);

d) Directional type: single directional.

Teaching and examination specific headphones, equipped with a single directional anti noise microphone and stereo high fidelity internal magnetic headphones: specially designed "copper platinum alloy" high tensile and anti bending spiral wire; using a 3.5mm interface, durable.