McIntosh has been perfecting tube amplifiers since the late 1940s and their transistor counterparts since the 1960s, with the brand's achievements having been used in such historic events as US Presidential inaugurations and the legendary Woodstock concert.
A legacy that has allowed the legendary New York firm to develop a unique audio amplification system destined to become the ultimate, no-compromise solution for bi-amping loudspeakers: the MC901 dual mono power amplifier. Dual mono" and not "dual mono" because, unlike any other mono power amplifier available on the market, the MC901 combines two power amplifiers, of different types, in a single chassis.
Specifically, a 300 watt continuous vacuum tube-based power amp (eight KT88s, four 12AT7s and two 12AX7As) and a 600 watt continuous transistorised power amp, with the former designed to reproduce the mid and high end of the spectrum and the latter to reproduce the low end of the spectrum.
The MC901's tube section uses one of the unique Unity Coupled Circuit output transformers (dating back to the founding of McIntosh in 1949) to ensure delivery of its full 300 watts to 8, 4 or 2 ohm speakers, while its solid-state counterpart uses another McIntosh exclusive, Autoformer technology, to perform the same task.
A key conceptual element of the MC901 is that its two amplifier sections have been designed to work synergistically, while being specifically developed to ensure that each (which includes its own dedicated power supply) amplifies only the frequencies it is designed to handle.
This unique configuration is managed by controls located on the top rear panel of the MC901, which allow you to adjust both the cutoff frequency and relative gain levels for each amplifier.
The MC901 is completed by a top-level construction presided over by the unmistakable treated glass front panel and one of the mythical analogue VU meters with blue background from McIntosh, adapted in this case to the uniqueness of this amplifier in the form of the Dual View, which includes two independent level meters, one for the "tube" section and one for the "solid state" section.
Features:
- Absolute reference hybrid dual hybrid "monophonic" power amplifier.
- Tube section with 300 W RMS for the middle and high end of the spectrum.
- Transistor section with 600 W RMS for the low range.
- Unity Coupled Circuit technology from McIntosh for the tube section.
- Quad Balanced technology from McIntosh for the transistor section.
- Output power immune to loudspeaker impedance variations.
- Crossover frequency and relative gain adjustment between sections.
- Power Guard Grid Screen protection system for the tube section.
- Sentry Monitor protection system for the transistor section.
- High-precision dual analogue display Dual View.
- Monogrammed Heatsinks in the transistor section.
- Balanced (XLR) and unbalanced (RCA) line inputs.
- Solid Cinch output terminals exclusive to McIntosh.
- 10-100,000 Hz frequency response for the transistor section.
- 10-70,000 Hz frequency response for the transistor section.
- 112 dB signal-to-noise ratio for the tube section.
- 122 dB signal-to-noise ratio for the tube section.
- Dimensions: 445x340x750 mm (W x H x D).
- Weight: 81.6 kg.
