The McIntosh Labs MC303 Three Channel Power Amplifier is a solid-state amplifier with 300 watts per channel. With every cutting-edge technology packed into its massive 155-pound chassis, it delivers tremendous audio quality and almost limitless headroom to drive the most demanding speakers.
McIntosh Labs MC303 Three Channel Solid State Power Amplifier Highlights
- Can be used as a three-channel amp in a high-end home theater.
- It can be used to tri-amp McIntosh’s own speakers.
- Power Guard® protection against clipping or over-driving the amplifier.
- Sentry Monitor™ fuse-less system to shut down amp to prevent short circuits and auto reset when conditions return to normal.
- Patented Autoformer™ which allows an ideal match from amp to speakers.
- McIntosh Labs’ world-famous blue meters.
- Polished glass front panel.
- Aluminum handles.
- Remote on/off with McIntosh pre-amp.
McIntosh Labs is among the founding companies that created high-end audio back in the late 40s and into the 50s. Owning a McIntosh amp was a statement that you were a well-funded audiophile and music lover who wanted the absolute best. The McIntosh MC303 Three Channel Power Amplifier has been in production for over a decade, and while many audiophiles may look beyond it because it is a three-channel amp, we set out to find out how accomplished it is for both home theater and two-channel music. In today’s world, many systems must do it all, and one should not have to compromise on either.
Power Output per Channel:
300W @ 2, 4 or 8 Ohms
Number of Channels:
Total Harmonic Distortion:
S/N below rated output:
Rated Power Band:
20Hz to 20kHz
+0, -0.25dB from 20Hz to 20,000Hz / +0, -3dB from 10Hz to 100,000Hz
Remote Power Control:
Multi-Channel DB25 Cable:
Push-Pull Complementary Autoformers
Meter Light Switch:
Glass with handles
LED Fiber Optic
Speaker Binding Post Type:
Unit Dimensions (W x H x D):
17-3/4″ (45.09cm) x 12-3/8″ (31.43cm) (including feet) x 22″ (55.88cm) (including front panel and cables)
155 lbs. (70.3 kg)
180 lbs. (81.6 kg)
mcintosh, mc303, power amplifier, three channel amplifier, solid state amplifier
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My first McIntosh amp is now 20 years old and works as well as the day it was new. It is the MA-6900 integrated, and I will never forget un-boxing it (still have the original box). It’s a 200 WPC (into any load from 2 to 8 ohms) amp that has been used with over 150 pairs of loudspeakers that have been tested here over the two decades. It’s bulletproof, and so well made that even my wife loves the look. The MC303 takes this concept to an even higher level. It is a drop-dead gorgeous work of art that can also make beautiful music.
One well-known design concept of McIntosh amps is the Autoformer™. Unlike most amps, which merely have positive and negative posts on each amp channel for the speaker wires, the MC303 has on the positive side the choice between 2-, 4- or 8-ohm loudspeaker outputs (along with a single negative, or common post). For difficult-to-drive, low-impedance loudspeakers, one would use the 2-ohm output post. Your McIntosh dealer will be happy to make sure you select the right post. Without getting into a 2000-word discussion (which is warranted, but space is lacking), you never have to worry that you don’t have the proper amp for the speakers of your choice; the MC303 will make sure that ample power is always available. Another plus is the gold-plated binding posts. They help complete the look of a high-end product, and the entire design of the MC303 had me thinking this is an upper-level McIntosh amp, how can it be this affordable?
Other useful features include Power Guard® protection that makes it virtually impossible to clip the MC-303. Sentry Monitor™ and Thermal protection to ensure one never overheats this amplifier and a highly regulated power supply that offers up exceptionally low noise and distortion.
The MC303, if one would use a single word to describe it, is “over-built.” It is 155 pounds of pure brute power that is designed to be your last-ever amplifier. Fifty-year-old McIntosh amplifiers are highly sought after, which is quite a testament to the quality of their products.
In addition to all this technology that brings almost unbreakable durability, the MC303 offers unbalanced RCA and balanced XLR inputs, available remote on/off with the optional 1/8-inch cable between a McIntosh pre-amp/processor and the power amp, and that world-famous glass front panel with blue meters. For sheer beauty, it offers a lot of glamour for its $12,500 entry price.
Occasionally, a reviewer gets to boast about doing something. In the case of the McIntosh MC303, the boast will be how I managed to unbox it and carry it to its primary listening position by myself. At 155 pounds, this was a challenge, but I was not to be denied. The handles on the MC303 did help, but be careful about trying this at home. The good news is your McIntosh store will almost certainly be happy to install it for you.
The set up was quite simple. The Rotel/Michi P5 pre-amp provided system control. The source was a Yamaha CD-2100S CD/SACD player. Interconnects from the Yamaha to the Michi and the Michi to the McIntosh were Blue Truth Ultra XLR cables, and speaker cables were two eight-foot runs of Blue Jeans Cables 10 AWG wire.
I used four different loudspeaker pairs to determine how flexible the MC303 is. Those speakers were the Harbeth SHL5 Plus XD monitors, the Sonus faber Maxima Amator, The Heretic Loudspeakers AD612, and for three-channel use, the Axiom M100/VP180 mains/center channel. Each of these speaker systems will represent a different challenge to the MC303. All of them have been well reviewed by our Staff at Secrets, and all are currently recommended components.
McIntosh Labs meets The Heretic Loudspeakers AD612
The Heretic AD612 loudspeakers were tested in our listening room in late 2022 and were a smash hit. The AD612s and their slightly smaller brother, the AD614s, have not only received a rave review from Secrets but several other magazines/webzines have also discovered that they are a tremendous loudspeaker. Highly sensitive at 97dB (2.83 Volts/one meter) and exceptionally linear across the bandwidth from 35Hz and up, the AD612s will not challenge an amplifier in terms of output levels. What they WILL do is allow one to hear if an amplifier is deficient in any way. In the case of the MC303, the first test was to listen for a noise floor. The verdict was simple: the MC303 makes no audible noise. It is as dead silent an amplifier as I have ever experienced. With that portion of the test having passed with flying colors, it was time to do some serious listening through the entire system.
Steely Dan “Aja”
Steely Dan’s “AJA” was selected as the perfect disc in which to explore the MC303 with the Heretic AD612’s. It’s an unusual collection from Steely Dan as it is meant to be played loud. Back in the late 70s, it was a standard disc used to test out a system’s limits. The opening track, “Black Cow,” will explode out of a system if the system can take it. The MC303 and the Heretics immediately proved to be a wonderful pairing. The opening bass line was some visceral HITTING in the chest fun, and I immediately sat back to enjoy the performance. On second thought, it was not “quite” immediate. I did have to make sure the subwoofers were not turned on, as the bass coming from the Heretics was even better than when I reviewed them last autumn. If anyone thinks McIntosh amps don’t do bass well, it’s time to re-think that notion.
The vocals had an ambience that I have never experienced at this level with thousands of listening sessions over the last 45 years with AJA. Every instrument was so well proportioned that goosebumps were present.
The title track has one of the most difficult drum solos ever recorded. Most speaker/amp combinations have a bit of smearing that isn’t noticeable until one hears it done right. The McIntosh amp and Heretic speakers do it right. Each “swack” is heard as one would typically hear when listening to live drums through this pairing.
The nostalgia continued through “Deacon Blues,” which was released in March 1978 as a single. It hit its peak about the time I graduated high school, which was both a sad and exciting time of life. Deacon Blues resonated with me the first time I heard it in 1978, and it still does. The McIntosh amp brought out all the emotion of this song to the point where I had to hit repeat for a second go. It was apparent from the specs that the MC303 is powerful. It is also a wonderfully detailed and musical piece of equipment.
McIntosh meets its cousin from Sonus faber
The McIntosh Group owns both McIntosh Labs and Sonus faber, an esteemed speaker company based out of Italy. As I purchased the review pair of Sonus faber’s Maxima Amator loudspeakers last year, it seemed a proper idea to pair these cousins up and make some music.
Vanessa Wagner “Study of the Invisible”
We started with Vanessa Wagner’s “Study of the Invisible.” She is considered by many to be the most accomplished classical pianist of her generation. “Study of the Invisible” is a sublime series of Vanessa performing 15 compositions from different artists. Picture yourself in a cozy listening environment, perhaps with a fireplace ablaze, and the only instrument is Vanessa’s piano. The performance is so deep and compelling that the small audience is silent.
Reproducing a piano with authenticity is one of the most difficult tasks for any audio system to undertake. If one can listen to a live, unamplified piano in a fairly intimate setting, one should take this opportunity. The McIntosh MC303 again demonstrated its prowess by bringing Ms. Wagner’s talents to light in a most believable manner. The range in octaves and the sheer volume of sound coming from this McIntosh amp through the Sonus fabers were inspiring.
The dynamics on this disc are well beyond what most of us ever experience outside live music, and here we were, being entertained with soft dynamics that encouraged us to lean into the music then crescendos that were, at times, startling. Vanessa’s talent is almost beyond words, and her timing on the keys is impeccable.
This speaker/amp combination also had a way of disappearing as a source. What I experienced was beauty, power, and emotion with little to no thought that an audio system was being engaged. That is the ultimate goal of a good audio system, and this MC303 amp proved it could anchor such a system with authority.
Supertramp “Brother Where You Bound”
After the performance of Vanessa Wagner, it was time for another challenge for the big McIntosh amp. Supertramp’s not-too-fond-of-government album from the mid-1980s “Brother, Where You Bound,” was up next on the MC303/Maxima Amator schedule. The two primary tracks from this CD are “Better Days” and the title track “Brother, Where You Bound.” The political rants probably are over the top, but as he makes fun of all things political, I can ignore it and enjoy the music.
This pair of songs beings hard-driving, well-recorded rock complete with vocals, keyboards, brass, and special effects. The MC303 did a remarkable job of bringing out the various politicians who are speaking in “Better Days,” while the brass and percussion are running in a blaze of glory. We then hit that title track, which opens with a tribute to Orwell’s “1984,” including some old radio tracks that come through with more clarity than I have heard to date. Even the Russian speaker, who typically is barely audible, is presented with total clarity.
The main body of “Brother” is filled with kick drums, guitar, piano, and the MC303 is wringing every bit of performance out of the seven-inch woofer that is possible. There was that “good bass” thing again.
MC303 meets the British Invasion from Harbeth
The Harbeth SHL5 Plus XD is known as a ruthless monitor in the BBC-inspired speaker design. I have owned a pair for two years now, and when combined with an amp of high current capability, they are some of the most musical speakers one can buy.
Crosby, Stills & Nash “CSN”
As I type this, it has been less than two months since we lost David Crosby, which made auditioning the 1977 album “CSN” from Crosby, Stills, and Nash a simple decision.
The disc opens with “Shadow Captain,” which immediately features the trio harmonizing in the manner which helped make them famous. The MC303 was again superb, with each of our singers coming across with proper spacing in front of the stage and a purity that lesser systems cannot begin to approach. The disc then goes into some wonderful acoustic guitar and more harmonizing. It’s the type of performance that calls one to the opposite of action, which means kicking back and taking it all in.
Fair Game wasn’t intending to send this message, but considering its late 70’s release, it’s almost a warning about the end of the sexual revolution and the consequences of “free love.” 45 years later it seems more like a bridge between free love and what happened with the AIDS epidemic of the 80s. The performance by Stephen Stills was relaxed in its delivery in 1977, becoming almost chilling in later years.
Of special note from this disc is “Dark Star,” a song about a man trying to reconnect with his wife after an elongated dark time in which they drifted apart. The McIntosh/Harbeth duo was spectacular in its ability to keep the perfect pace that this song deserves. On most systems, it sounds pretty good. On a great system, it becomes most emotional, and one finds oneself hoping his Dark Star opens that smile and lets him back in.
The MC303 has proven itself to be an outstanding example of a two-channel amplifier with no audible faults with stereo reproduction. Now it’s time for the other side of the possible performance with this amp anchoring the front speakers in a high-end home theater system.
MC303 Goes to a Three Way with the Axiom M100s and VP180HP
The MC303 is a three-channel amplifier, and so far, we have only explored its use in some two-channel systems. What about home theater, in a system in which one wants both first-rate music combined with the best in surround sound? The speakers in question are the Secrets of Home Theater and High Fidelity recommended Axiom M100s and the matching VP180HP center channel. This trio of Axiom speakers has a total of eight 6.5-inch-long throw woofers in cabinets tuned to about 32Hz. After some consideration, I decided to really put the MC303 to the test: we ran a 3.0 home theater system with all bass running through the Axiom speakers without a separate subwoofer. This is a real torture test for both the speakers and the amplifier. In terms of sheer cone area, these eight woofers are comparable to a pair of 12-inch woofers.
We began with “Open Range,” a classic western with one of the finest subwoofer tests in the history of home theater. Not only do Kevin Costner and Robert Duvall have wonderful father/son chemistry, but the whole movie also makes for a great Western. The early scenes were fantastic through the MC303/Axioms, with detail in abundance. The dialogue was crystal clear and the rainstorms rife with palpable thunder and rain so clearly heard that I checked the windows to make sure it wasn’t really raining. It’s the gunfight scene at the end that separates the pretenders from the contenders in terms of believable power. I am used to quad 12-inch drivers with 3500 watts of AB power applied and was expecting a serious degrading of the shock value this scene delivers. I was pretty pleased with the results: while we weren’t getting as much in terms of chest-concaving bass with the Axiom speakers as the subwoofers deliver, it was closer than expected. The MC303 may have a lot of manners, but it can also hit hard when the need is there!
We finished the listening tests with 2018’s “Bohemian Rhapsody.” Rami Malek brought Freddie Mercury to life in this film, and the music tracks are so well recorded that putting this system to the test with Queen was an easy decision. The McIntosh MC303 again showed itself to be a bomb-proof amplifier, bringing all the concert scenes into our living space with ear-tingling perfection. My personal favorite was the audience stomping to “We Will Rock You.” This 3.0 system hit HARD into one’s chest and made me realize I could live without a subwoofer if bass could be presented like this. The MC303 showed it could handle anything we could throw at it. Vocals were always pristine, brass instruments had bite without harshness. Drums were delivered with authority and guitars had endless dynamics.
For $12,500, the McIntosh MC303 Three Channel Power Amplifier is a significant purchase, but you’re getting unmatched performance in a component built for life.
- Seemingly unlimited power
- Cool running
- Incredible detail
- Drives any impedance load
- Gorgeous at every angle
- Even non-audiophiles love the name
- Versatile for music and home theater
- Try to clip it. I dare you!
- Deep and wide sound stage
- Someone else carrying the next McIntosh amp into my home
McIntosh has become a company that not only offers great products but also offers great value as well. In a world where many quality power amplifiers can set one back over $25,000 and even into six digits, the $12,500 price for this wonderful sounding, powerfully performing, gorgeous looking amplifier seems to be a bargain. There may be some people at their factory in Binghamton New York facility wondering “Did this Chase guy just call us a good value? He can’t do that! We are high-end!!” To those fine folks: don’t take it as an insult. This amplifier is an incredibly well-built beast that can handle anything I threw at it. The fact that you are charging a more than reasonable price is OK.
Having owned a McIntosh MA6900 integrated amp for 20 years, I already had a good feel for how timeless a McIntosh amp is. I have beaten on the MA6900 in countless speaker tests, and could never get it to do anything bad. The MC303 takes this to a new level with even better dynamics and more powerful bass. At $4,167 for each of its 300-watt channels, it isn’t inexpensive. It does offer a lot of value in the ultra-high-end world of audio. Part of the allure of products from companies like McIntosh is the pedigree. People recognize a Rolex, a Mercedes, and a McIntosh amp. Rolex and Mercedes wish they had as bulletproof a design as does a McIntosh product. In my reference system, I currently have a Cambridge Audio Edge W power amp, a Michi S-5 power amp, a Rogers Fidelity KW-88 integrated tube amp, a NAD M33 integrated amp, and the previously mentioned McIntosh MA6900 integrated amp.
The McIntosh impressed me enough with its sound quality that it, along with the Rogers tube amp, is now a part of my reference amplifiers. The McIntosh MC303 will not be returned to the company, as I am purchasing it. The final decision on this was made over the last few days when I had the opportunity to do some listening to a recently received pair of Legacy Audio Focus XD loudspeakers. As good as the rest of my amps are, the McIntosh delivered the highest level of sound quality yet through the Legacy speakers, which will be the subject of a full review later this year.
If you are thinking about an upgrade in amplifiers, give McIntosh a good look. They have a wide variety of products, including many that are more affordable than the MC303. While other companies may offer “more watts per dollar,” McIntosh will likely offer more years per dollar than anything you can find. Thanks for reading this far, it’s time for me to listen to some jazz while watching those blue needles bounce.