Усилители мощности стерео — McIntosh MC312

The McIntosh MC312 is a stereo transistor amplifier intended by the maker for both stereo music systems and home theater. It belongs to the SoHo II Music System range and replaced an earlier McIntosh model of the same power class, gaining a larger power supply reserve and several cosmetic and circuit updates.

Key specs that matter

Rated output holds at 300 W into 2, 4 or 8 ohm loads. Total harmonic distortion is 0.005%, with noise 120 dB down through the balanced inputs or 118 dB through the unbalanced ones. Dynamic headroom is 2.3 dB, and the wideband damping factor exceeds 40. Frequency response stays within +0 and -0.25 dB between 20 Hz and 20 kHz, and within +0 and -3.0 dB between 10 Hz and 100 kHz, with a rated power band of 20 Hz to 20 kHz. Width is 44.45 cm, height 23.97 cm including feet and depth 55.88 cm counting the front panel, handles and cables. The amplifier weighs 47.63 kg on its own with a boxed weight of 62.59 kg.

Engineering and use context

Its push-pull complementary transistor stage drives McIntosh Autoformers, which are output transformers that let the amplifier deliver the same rated power regardless of speaker impedance. Filter capacity was doubled compared with the predecessor, lifting dynamic headroom from 1.8 dB to its current value, an increase of 27%. Power Guard monitors the input signal and adjusts it to prevent clipping. Short circuits are handled without fuses by Sentry Monitor, a protection scheme that resets itself automatically. Heat is handled by Monogrammed Heatsinks. The chassis of polished stainless and black-painted steel carries a black glass front with direct LED backlighting, an illuminated logo and blue watt meters whose lighting can be switched. New enclosures for the transformers include glass inserts printed with wiring diagrams, and aluminium end caps finish the sides. Internal circuits and wiring were upgraded, and an energy-saving circuit switches the unit off after a period without signal. Neither mono bridging nor mono parallel operation is offered. Solid Cinch gold-plated binding posts keep speaker cables from working loose. The warranty is a 3-year limited one.

Pairing

A preamplifier connects through two XLR or two RCA inputs, and XLR and RCA outputs of both types can feed a further amplifier for bi-amping or tri-amping. Remote power control links it to other McIntosh sources such as CD players, turntables, tuners and media streamers so the system powers up together.

Alternatives

The McIntosh MC462 is the stronger stereo model from the same solid-state range, rated at 450 W per channel.