Интегральные усилители — McIntosh MA12000

The MA12000 is a stereo integrated amplifier in which McIntosh drives a solid-state output section from a preamp built around vacuum tubes, and it also contains a digital module and a phono stage. McIntosh calls this layout Hybrid Drive. The preamp section runs on four 12AX7A tubes, two per channel, and the unit offers 17 inputs in total, 10 analogue and 7 digital. It carries a 3-year limited warranty and is Roon Tested.

Key specs that matter

Rated output is 350 W per channel into 2, 4 or 8 ohm, with dynamic headroom of 1.5 dB and a damping factor above 40. Amplifier distortion is 0.005%, and the preamp stage is rated at 0.03%. Frequency response is 20 Hz to 20 kHz within 0.5 dB and 10 Hz to 100 kHz within 3 dB. Signal-to-noise is 114 dB for the power amp input, 95 dB for high level inputs, 77 dB MM and 75 dB MC. Line inputs are two balanced at 44 kohm and six unbalanced at 22 kohm, with sensitivities of 600 mV and 300 mV. The chassis is 445 mm wide, 240 mm high and 502 mm deep, and weighs 48.9 kg.

Engineering and use context

Output transformers called Autoformers keep rated output constant across these loads, and Solid Cinch gold-plated binding posts take the cables. The DA2 digital module uses a quad balanced 8-channel 32-bit/384 kHz converter. USB accepts DSD up to DSD512 and DXD at 352.8 and 384 kHz, the two coaxial and two optical inputs take up to 24-bit/192 kHz, and there are an MCT input for McIntosh disc transports and an HDMI ARC connection. The MM and MC phono inputs have adjustable loading, with sensitivities of 3.0 mV and 0.30 mV. Power Guard adjusts the signal in real time to prevent clipping, and Sentry Monitor gives fuse-less short-circuit protection that resets itself. An 8-band tone control can be bypassed, and the High Drive headphone output includes the HXD crossfeed circuit. The glass-topped enclosure combines polished stainless steel with black painted steel and carries two peak-responding blue Watt meters.

Pairing

Outputs include balanced variable, unbalanced fixed and unbalanced variable, so a subwoofer or recorder can be added. Home Theater PassThru lets the amplifier sit inside a surround system, and power control and trigger outputs, RS232 and IR inputs support system control.

Alternatives

The McIntosh MA9500 is a solid-state integrated amplifier rated at 300 W per channel with the same DA2 digital module.