Усилители мощности стерео — McIntosh MC2152 70TH ANNIVERSARY

The MC2152 70th Anniversary is a stereo vacuum tube power amplifier McIntosh built to mark seven decades of the company, which was founded in 1949 around its patented output transformer design. It pairs a traditional tube circuit with a deliberately modern look - a bead-blasted black anodised aluminium chassis, matte carbon fibre side panels and a backlit laser-cut McIntosh logo - instead of the brand's usual polished steel and glass. It was priced at around USD 15,000.

Key specs that matter

The MC2152 delivers 150W per channel into 2, 4 or 8 ohms with less than 0.5% distortion. It uses sixteen tubes in total - eight KT88 output tubes, four 12AX7A and four 12AT7 small-signal tubes. The two output transformers sit at the rear with the power transformer between them, all three housed in glass-topped extruded enclosures printed with each transformer's wiring diagram. The tubes are protected by a 12-gauge stainless steel wire cage with black powder-coated finish.

Engineering and use context

The central technology is McIntosh's Unity Coupled Circuit. Its output transformer uses two bifilar-wound primaries, one for the cathodes and one for the plates, with the secondary wound together with them. This multifilar winding gives very close coupling between primary and secondary, which McIntosh credits with low distortion, flat frequency response, wide power bandwidth and relatively cool running of the output tubes. The secondary is tapped for different loads, which is how the amplifier holds its rated power across all three impedances. McIntosh's Sentry Monitor tube protection circuits guard the output stage and are intended to give the amplifier a long, trouble-free life. LEDs under the eight small-signal tubes can be switched between off, green and red. Running eight KT88s means substantial heat and power consumption, so the amplifier needs open space above and around it rather than an enclosed cabinet.

Pairing

As a power amplifier, the MC2152 needs a separate preamplifier, and McIntosh's own tube or solid-state preamplifiers are the natural visual and functional partners. The output taps let the amplifier be matched to the speaker's nominal impedance, and it has the power to drive most floorstanding loudspeakers of ordinary sensitivity in medium to large rooms.

Alternatives

McIntosh's own MC275 is the brand's long-running KT88 stereo tube amplifier in a smaller 75W per channel format with the classic polished chassis.