Using a DLP 3D printing cavity. Headphone jack 3.5 mm Jack. Excellent Objective Indicators: ZERO has a proper low-frequency gain and high-frequency response in line with HRTF characteristics, which makes ZERO own the objective index comparable to that of professional monitor earphones, while it is not as cold and rigid as that of common monitor earphone, and its overall timbre is natural and full of atmosphere.
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