SMSL Black H400 Fully Balanced/Unbalanced High Power Headphone Amplifier 15Wx2/16ohms Preamplifier. - Output power: 15W x 2 at 16ohms; 7.5W x 2 at 32ohms; 1000mW x 2 at 300ohms; 550mW x 2 at 600ohms. - Preamplifier output mode: balanced, unbalanced.
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