HIFIMAN EF400 Headphone Amplifier with Built-in DAC / R2R Design. HIFIMAN EF400 Headphone amplifier / Amplifier with built-in DAC / R2R design / Low power consumption Output. The HIFIMAN EF400 is a music-oriented audio device that integrates a built-in R2R DAC and a high-power amplifier, and its simple design with only USB input makes it ideal for listeners who value sound quality and users of high-end headphones.
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