McIntosh MC611 Quad Balanced Power Amplifier Review

The arrival

The dog raised his head from where he had been sprawled out on one of the living-room rugs and looked at me with what appeared to be real fear in his eyes.

A minute later my son walked in all the way from his room at the back of our spread-out bungalow and yelled over the music “What’s going on man?”

I was sitting pressed back into the sofa a good 18 feet from the speakers with what I’m sure was an expression not too far from that of our Pekingese Yorkie. I glanced sideways at my son and pointed at the sparkling new glossy-black and stainless steel McIntosh MC611s ($15,000 USD/pair) with their glowing blue meters bouncing wildly at the far end of the room and said, “Riiiiiight!!!???”

He peered at them, shook his head and left. I barely made out a door slam in the distance over the deep bassline that seemed to be flexing the shuttered floor-to-ceiling windows down the long side of the room on my left.

The Shy “Invisible/Amenaza” was playing off a Scott Eastlick 16/44 mix and my two-way Audio Note AN-E/SPe HE loudspeaker’s mid-bass drivers seemed to be at their excursion limit, but there was no distortion, nothing remotely fatiguing about the sound. It just enveloped me completely and seemed to be pressing down against me physically, albeit not uncomfortably.

All I could think of at first while I was listening to the mix progress was an interview with Star Trek director, JJ Abrams, where he talked about shooting the establishing sequence of the U.S.S. Enterprise in the film. In the shot the ship is sitting in space dock orbiting the Earth as Kirk and Bones approach it in a shuttle and see it for the first time. Abrams decided to use a cinematography trick where the camera frames a very large object of interest too tight, so that – as in reality – when one is confronted with something the size of an aircraft carrier it appears cut off around some of the edges. The reason? To create an illusion of scale so large that the viewer simply cannot take it all in at once.

Why was I thinking of this? Because the scale of the sound from the McIntosh MC611 mono blocks seemed too large for my home at first, I had to adjust my perception of the spatial capabilities of what an amplifier could deliver through my loudspeakers and what the room could handle from a pressurization standpoint. It’s a good-sized room, measuring roughly 13x24 feet and opening out onto a dining area along part of one the long sides, also the ceilings slope from 10-feet to a 14-foot peak. I was looking forward to hearing just what the big McIntosh amps were capable of.

The MC611s arrived incredibly well-packed, multi-boxed and with internal wood bracing/framing that each unit was bolted to for transport. The whole “container” for the amps during delivery is one of the most well-engineered shipping vessels I’ve come across and further polishes McIntosh’s image in my mind as a company who leaves nothing as an afterthought, because you literally need instructions for unboxing or packing up the boxes once the amps have been removed and set up. Be forewarned, you need two people to properly place the 611s as each amp ships at 130 pounds of dead weight.

The fit and finish of the amps is exemplary. It is something to behold in person and speaks to McIntosh's innate appeal and recognition by many both in and out of high-fidelity circles. The fact that a 100 pound amplifier can be lifted or moved with no discernible flex or torsion speaks to advanced engineering prowess both within the circuit confines and that of the chassis that holds everything together. Looking at and touching the 611 it feels more like artwork than technology with its smooth stainless steel side rails, mirror-polished glass fascia, and gold-embossed matt-black finished chassis enclosure do nothing to dissuade one from constantly thinking this.

Establishing a baseline

One of the first things I wanted to establish was the review baseline for the mono blocks. So I did some tests to gauge how transparent the McIntosh C2600 tubed preamplifier I was using with the MC611s was compared to just jacking the DACs directly into the mono blocks – via unbalanced or balanced – depending on the DAC.

Over the next several days I played more and more music. I had long listening session after long listening session using the totaldac d-1 direct. I swapped AC cables on the 611s, the C2600 and then started adding some other DACs to the mix. Everything was being fed clean power courtesy of a PS Audio DirectStream P20 regenerator.

On the DACs I decided to narrow down the review listening to, I swapped between USB, SPDIF, balanced and unbalanced interconnects to see which I preferred. I swapped ethernet cables from my dedicated, audio-use only router, I swapped out my dedicated audio-use only MacBook Air 11-inch for an Aurender N10 and a dCS Bridge and continued to listen to the differences between DACs to measure how adept the 611s were at translating the dialects of sonic language each was speaking through them. It was my own United Nations in miniature.

Every change I made in cables, or what surface the preamplifer, servers and DACs were placed on, no matter how minute – even implementing different isolating cones under the dCS Debussy or the totaldac d-1 direct for example – was instantly passed along to my ears through the 611s. I’d like to touch on how quiet these amplifiers are. I’m not one for listening with my ears a couple inches from a tweeter, but with the volume set at *50 through the 2600, I could only hear a faint hiss issuing forth. In my experience it is this deep-black background which helps allow more low-level texture, detail and micro dynamics to come through from a recording, something the 611s excelled at with every type of music I listened to through them.

*My average volume listening setting is between 30 and 45.

So, after many A/B comparisons I decided to use the C2600 as the go-between for everything using TelluriumQ Ultra Black XLR cables from the preamp to the 611s as the 2600 is, for all intents and purposes, practically transparent in passing along the signal. The fact that you could tube roll it for sonic flavouring only adds to its appeal.

All the digital cables (USB, SPDIF, digital RCA), RCA, XLR and ethernet used in the review were a mix of TelluriumQ Black Diamond, Ultra Black, Black and Silver. AC cables used throughout were Clarus Crimson and speaker cables were Audio Note bi-wired Lexus 96.

Initial listening was done through the MacBook with Roon, but after swapping in the Aurender N10 I started using their dedicated Aurender app, ditto for when using the dCS Bridge and their dedicated dCS app. I know Roon, I love Roon, but I wanted to spend time with another music player app and see what both dCS and Aurender were bringing to the table and both – while not as all-encompassing in their capabilities as Roon – were easy, straightforward and in the end for me, as capable for everyday use. As with all such matters of preference, YMMV.

Screenshot of the Aurender App in use.

Screenshot of the dCS Bridge App in use.

For my gear support I used a 48-inch George Nelson wood bench after getting rid of my previous steel and glass racks as I overwhelmingly preferred the sound of all my gear on wooden support structures whenever possible. Regardless of its plain looks, it works more than well enough for my review purposes as I wait for a custom credenza to house gear to be finished being built.

After a couple weeks getting used to the 611s through my AN-Es (spec’d at 97.5 dB, 23kHz~18Hz @+/-6dB, six-Ohm nominal impedance) I added in a pair of ELAC Adante AS-61 stand mounts that Vancouver’s Hi-fi Centre loaned me, as I wanted to see how the big McIntosh’s would play with something more difficult to drive (Adantes spec’d at 85dB, 41kHz~35Hz, six-Ohm nominal impedance).

During their time with the ELACs, the 611s barely broke a sweat driving the Adantes to their limit over extended listening sessions. With more than 1,400 square-inches of heat-sink area available for convection cooling, the amps never became hot to the touch. In fact they barely got more than warm to the touch when idle and when on-power with a demanding load they never, ever got close to hot during any of my listening sessions.

COMPANY INFO
McIntosh Labs Inc.
2 Chambers Street - Binghamton, NY 13903-2699
1-607-723-3512
ARTICLE CONTENTS

COMMENTS
enjoythemusic's picture

You bought the review sample from McIntosh? Am noticing a trend that reviewers are buying Mc gear.

Rafe Arnott's picture
After living with the 611s, they proved themselves to be exactly what I need moving forward.
mentt's picture

Thank you for nice long review. Nowadays some reviews are written after couple of hours of listening in dealer showrooms. It is good that somebody still does the true reviews. Good job

Rafe Arnott's picture
For the kind words Mentt, it was my hope to do as thorough and in-depth of a review as I was capable of.

Having enough proper gear and cabling on hand helps tremendously because then I'm able to give readers a very clear, wide-ranging comparison of what each review product is capable of.

Lots more to come!

geoffreyvanhouwaert's picture

Hello,

Indeed a nice in depth review. Thanks. Writing reviews myself i know how much work goes into them. Learning a lot from this one.

Best regards
Geoff

Rafe Arnott's picture
Thanks for taking the time to thank me for the work that went into this review. It's truly appreciated.
bobflood's picture

Keep them coming like this.

Rafe Arnott's picture
I'll keep rolling them out. Very happy you enjoyed it.
RKeller1007's picture

Great review. Interview with McIntosh CEO was very informative. Enjoy the work you have done Rafe.

Leffen's picture

Amazing review. I keep coming back to check for more ! big ups

ps i wanna use this as a guitar amp :}}}}}

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