MC1.25KW Monoblocks

Redesigned from top to bottom, the MC1.25KW replaces the venerable MC1.2KW as McIntosh's most powerful single chassis monoblock amplifier. (Price for a pair)


3 year warranty

MC1.25KW Monoblocks


The MC1.25KW Quad Balanced Power Amplifier is McIntosh's newest and one of their most advanced amplifiers. Redesigned from top to bottom, it replaces the venerable MC1.2KW as our most powerful single chassis monoblock amplifier. A simple glance at this 158 pound (71.7 kg) amp is enough to convey its power and performance capabilities, but when you hear it – then you’ll truly understand what it can do.

The MC1.25KW outputs 1,200 Watts of pure power into a single channel with a nearly imperceptible total harmonic distortion of 0.005%. This astonishing amount of power is fully available to 2, 4 or 8 Ohm speakersvia our Autoformer™ technology. A pair of these amps can anchor a home audio system that can rival nearly any stereo system in the world.

Updates and enhancements abound in the MC1.25KW. A 50% increase in filter capacity improves the performance of low end frequencies as well as increasing dynamic headroom. The top of the amp showcases an updated yet unmistakable McIntosh industrial design that will fit right in with current McIntosh products or those made decades ago. The audio Autoformer and power transformer remain located just behind the front panel but are now contained in new glass topped enclosures. In between them is new circular glasswork housing the amplifier’s name badge that is adorned with a decorative trim ring.

The rear of the unit features 4 McIntosh Monogrammed Heatsinks™. Made from high quality materials with excellent thermal conductivity properties, these heatsinks are so efficient at dissipating heat that they warrant bearing the McIntosh “Mc” logo. They connect to advanced high current output transistors that eliminate thermal equilibrium lag time so that the first musical note played sounds just as good as songs played later in your listening session. The heatsinks are capped with handsome ventilation trim plates. These trim plates and the circular trim ring are made from aluminum and are finished to match the front panel handles. The AC receptacle has been repositioned to provide additional clearance so a wider assortment of power cords can more easily be used. All of this sits atop a polished stainless steel chassis which rests on 4 new redesigned feet that feature a chamfered edge. Other updates include an updated power transformer, heavier gauge internal wiring, upgraded circuit components, and the addition of our power management system that will turn the amp off after a set amount of time when no input signal has been detected.

With all the changes and improvements made in the MC1.25KW, one thing that hasn’t changed is the large, fast responding 11” (27.9 cm) blue Watt meter that accurately shows the amp’s power output. Also unchanged is the signature black glass front panel with control knobs, illuminatedlogo, and aluminum end caps with handles. The front panel and meter have new direct LED backlighting for improved appearance and color accuracy.

Other exclusive McIntosh features included in the MC1.25KW include:

Power Guard® that monitors and adjusts the output signal at the speed of light and makes real time adjustments to prevent harsh sounding and potentially speaker damaging clipping

Sentry Monitor™ – our fuse-less short-circuit protection circuit that disengages the output stage before current exceeds safe operating levels and then resets automatically when operating conditions return tonormal

Quad Balanced design that cancels virtually all noise and distortion that may have crept into the audio signal

Power Control to send power on/off signals to other connected McIntosh components (such as CD Players, turntables, tuners​ and media streamers​) for easy system power up and shutdown

Patented Solid Cinch™ speaker binding posts that easily but securely attach the speaker cables​ to prevent them from coming loose and possibly causing a short; the binding posts are also gold-plated to prevent corrosion and ensure a quality signal is sent over your speaker cables

Both a balanced and unbalanced output are included to make bi-amping or tri-amping your speakers easier; they can also be used to send the audio signal to a secondary system if your preamplifier does not have enough outputs or to connect a powered subwoofer.

*Price shown is for a pair

Tech spec

Output load impedance

Terminals for 8, 4 and 2 ohms

Rated power band

20Hz to 20kHz

Total harmonic distortion

0.005% maximum harmonic distortion at any level from 250 milliwatts to rated power output.

Dynamic headroom


Frequency response

+0, -0.25dB from 20Hz to 20kHz

+0, -3.0dB from 10Hz to 100kHz

Input sensitivity

2.5V Unbalanced, 5V Balanced

A-weighted signal-to-noise ratio

120 below rated output, Unbalanced

124dB below rated output, Balanced

Intermodulate distortion

0.005% maximum if instantaneous peak power output does not exceed twice the rated output, for any combination of frequencies from 20Hz to 20kHz

Wide band damping factor

Greater than 40

Input impedance

10,000 ohms

Power guard

Less than 2% THD with 14dB overdrive

Power requirement

100 volts, 50/60Hz, 13 amps
110 volts, 50/60Hz, 12 amps
120 volts, 50/60Hz, 12 amps
220 volts, 50/60Hz, 7.5 amps
230 volts, 50/60Hz, 6.5 amps
240 volts, 50/60Hz, 6.5 amps
Standby: 0.5 watts

Overall Dimensions (H x W x D) including feet and cables

2-5/16 inches (31.27cm) x 17-3/4 inches (45.09cm) x 22 inches (55.88cm)


147 pounds (66.7 kg) net

172 pounds (78.0 kg) in shipping carton

For more information click here to visit the McIntosh website


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