McIntosh MC1502 Vacuum Tube Amplifier, for any pair of loudspeakers out there
The MC1502 shares the timeless styling of classic MC275 Vacuum Tube Amplifier. As the MC1502 has twice the stereo power rating of the MC275 (150 Watts vs. 75 Watts) and is physically larger, in many ways it can be considered the MC275's big brother. And while a pair of MC275s can be run in mono to achieve the 150 Watts per channel output of the MC1502, the MC1502 boasts a better signal-to-noise ratio of 112dB vs. 105dB for the MC275 pairing producing an even quieter performance than the already quiet MC275.
The MC1502 is powered by eight KT88 output vacuum tubes, with four assigned to each stereo channel. It also has eight small signal tubes, consisting of four 12AX7A and four 12AT7 vacuum tubes; two of each of these vacuum tubes are dedicated to each audio channel. The 12AX7A vacuum tubes are for the Balanced and Input amps, while the 12AT7 tubes are for the Voltage and Driver amps. All the vacuum tubes are covered by a 12-gauge stainless steel wire cage with a black powder coated finish.
The KT88 vacuum tube sockets include Air-Pipe cooling at their bases to help facilitate long service life. The eight signal tube sockets have ceramic base construction with gold plated contacts, providing protection from atmospheric contamination. All the vacuum tubes sit atop the precision formed stainless steel chassis polished to a mirror finish. Sentry Monitor technology monitors the output current and shuts the amplifier off if it ever exceeds safe limits; the signal tubes will flash red if Sentry Monitor is ever activated.
Unlike many other amplifiers, the MC1502's full 150 Watts can be delivered to almost any pair of speakers regardless if they have 2, 4 or 8 Ohm impedance. This is thanks to patented Unity Coupled Circuit output transformer technology – the same technology McIntosh was founded on in 1949. Two Unity Coupled Circuit output transformers flank the power transformer which is positioned between them. Each transformer is housed in a glass topped extruded enclosure that displays the wiring diagram for each transformer. Two fully spelled out vintage die cast aluminum name badges adorn two sides of the MC1502, while an abbreviated badge is centered between the Tube Lights and Power knobs. ■