Drop + SMSL. Headphone outputs: XLR 4-pin, 6.35 mm unbalanced. Amplifier output impedance: Near 0 ohms. Frequency response range: 20 Hz – 100 kHz (-0.5 dB). Power consumption: <30 W. Gain settings: Low (-12 dB), Middle (0 dB), High (+12 dB).
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