It can be used with combined power amplifier, pure power amplifier and active speakers. Active subwoofer support: Yes. Technical index. 6.3V signal tube: 6N11, 6N1P, E88CC, E188CC, CCA, 6922, 6H23, 6H6, 6H30, (6SN7 needs to use 6SN7 to 6922 conversion seat).
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