High sensitivity:For the friction current of metal, pinch of the high-impedance input end with your hand, and the other metal with greater friction (metal door frame, water pipe, etc.), you can hear the rustling current from the headphones. Single tube amplifier suitable for electronic production: The impedance of the single tube amplifier is relatively high, and the use of high impedance headphones can effectively improve the output sensitivity. High impedance headphones are used in radio production and ore radio. Suitable for use in low-power audio amplifiers (low current * high impedance =high output power). The impedance transformer uses an isolation transformer, which can eliminate common ground interference and current noise. Specification: Size: 40x55x15mm / 1.57x2.16x0.59inch Material: Aluminum Package Includes: 1 Piece Impedance Converter : 1. The converter converts ordinary low-impedance earphonesinto high-impedance characteristics, and thus is used in high-impedance circuits. 2. Not suitable for low-impedance circuits, the volume becomes smaller instead (impedance mismatch). 3. The converter is suitable for headphone conversion, not for high power conversion.