Предусилители — McIntosh C12000

The C12000 is a two-channel preamplifier from McIntosh that combines vacuum tube and solid-state circuits and splits them across two chassis. The C12000ST holds the audio circuitry, the C12000C holds the controls and power supply, and shielded umbilical cables join them so that the pair works as one unit by remote handset or front controls. The aim of the split is to isolate the signal path from control and supply circuits.

Key specs that matter

There are 12 analog inputs - six balanced, four unbalanced and two phono inputs that can each be set for moving coil or moving magnet. Outputs are one balanced tube, one balanced solid-state, one fixed unbalanced and one programmable unbalanced, plus a 6.3 mm High Drive headphone jack. For the line stage, voltage gain is 15 dB, sensitivity 900 mV balanced and 450 mV unbalanced, input impedance 50 kohm and 25 kohm, maximum output 20 V and 10 V RMS, total harmonic distortion 0.005% and signal-to-noise 107 dB. Phono gain is 58 to 64 dB for MC and 40 to 46 dB for MM, in 6 dB steps, with phono distortion of 0.05% and signal-to-noise of 79 and 83 dB. Response is +0, -0.5 dB from 20 Hz to 20 kHz and +0, -3 dB from 10 Hz to 100 kHz. Each chassis measures 44.45 x 15.24 x 45.7 cm, the controller weighs 12.3 kg and the audio unit 11.3 kg, and power use is 75 W.

Engineering and use context

Hybrid Drive lets the owner choose between a vacuum tube or solid-state output stage. The high-level section uses six tubes - two 12AT7 and one 12AX7A per channel - and the phono stage uses four 12AX7A in a fully balanced RIAA circuit. Left and right channels are kept separate electrically and mechanically in a dual mono layout, and the balanced topology rejects common-mode noise. Both phono inputs have adjustable resistance and capacitance loading. Inputs can be level matched by up to 6 dB either way. The headphone jack includes the Headphone Crossfeed Director, and a Home Theater Pass Through lets a surround processor share the front channels. For system control there are RS232 inputs, a main power control output, two output control connections, four trigger outputs, eight data ports and IR sensor inputs. The chassis is mirror-polished stainless steel with brushed black titanium accents, and only the C12000ST carries output meters behind its black glass.

Pairing

The high balanced output level and six XLR inputs suit a fully balanced system, and the two balanced outputs can drive a stereo amplifier together with a subwoofer, or a pair of amplifiers in a bi-amp setup. The two phono inputs allow one MC and one MM turntable without an external stage.

Alternatives

The McIntosh C2800 is a vacuum tube two-channel preamplifier with 16 analog and digital inputs and decoding up to DSD512.