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The FiiO AM5 is a headphone amplifier module, similar to the AM2 with high power output. The FiiO AM5 comes with TPA6120A2 - a current feedback differential input high fidelity headphone amplifier with integrated circuit usually applied on desktop device. It is a headphone amplifier chip to achieve low distortion, higher bandwidth and higher slew rate. In combination to this, it effectively lowers the output impedance of the chip, TPA6120A2 so as to lower the amp output impedance to the maximum level. Capable of ultra high current for highly-dynamic musical performance and hardware-level adjustable gain to cater to different headphones.