Recently I reviewed the new NAD Master Series M17 AV preamp/processor, in which I indicated how impressed I was with its build quality, its features, and most importantly its sound quality. NAD also sent me the Master Series M27 seven-channel amplifier. With a retail price of $3,999, the M27 is a competitive alternative to many high-quality seven-channel amplifiers, or two-plus-five-channel amplifier combinations. Once I completed my review of the M17 using my reference Halcro MC70 amplifier, I substituted in the M27 to evaluate its performance.
The casework for the M27 is very similar to that of the M17. I go into extensive detail on this design in the processor review; but, to paraphrase, the build quality is a step above the norm, and the appearance is smashing. A huge departure from past NAD products, these Master Series products are real lookers.
The M27 is capable of 180 watts of continuous power per channel, with all channels driven, with a 20 Hz to 20 kHz frequency response and 0.005 percent Total Harmonic Distortion + Noise. Dynamic power is rated at 700 watts at four ohms. The result is the most powerful NAD amplifier to date. Other features include fully balanced and single-ended inputs (along with toggle switches to choose input type per channel), high-quality speaker binding posts, a 12-volt remote trigger for processor on/off control of the amplifier, and magnetic coasters for the cylindrical feet (just like the M17).
What is different on this amplifier, compared with previous NAD products, is the implementation of Class D amplifier technology licensed from Hypex of The Netherlands, from its state-of-the-art nCore line. Hypex is one of several companies that develop Class D amplifiers, but its technologies are the only ones found in notable audiophile products like the Rogue Pharaoh, B&W Zeppelin, and $12,000 Theta Prometheus mono block. The distinction here is that NAD does not purchase Hypex amplifier modules, but rather designs a homegrown amplifier that utilizes Hypex nCore technology through a license agreement. NAD has implemented some of its own design technologies, too--including the input stage and the switching power supply called PowerDrive--but the Hypex self-oscillating output stage, which is a big portion of the nCore advantage, is utilized.
Class D amplifiers have had a rocky start in audio applications, but they have gained traction in recent years as the technology has matured. Some of the benefits of Class D amplifiers are power efficiency, compact size relative to the power rating, dynamic power delivery, audio performance (more recently), and lower cost.
I used the same music and movie soundtracks that I used in the M17 review when the Halcro was in place. I started with the Fleetwood Mac Rumors album. At first listen, I could tell this was going to be difficult. The NAD sounded fantastic, but so did the Halcro. I forged ahead, and over time I was able to discern the traits of both amplifiers. On the CD track "Never Going Back Again," the guitar strings were spectacularly clear with the M27. Lindsey Buckingham's vocals had more presence, due to improved forward imaging. On the same CD, the song "Don't Stop" displayed cymbals with increased clarity that sparkled without the normal smearing that I, up until this point, thought to be a deficiency of the recording. Another track on this CD, "Songbird," always performed well with the Halcro MC70, but it sounded slightly more impressive with the NAD. Christine McVie's vocals were more pronounced, providing a realistic quality, yet it was not overbearing or in your face. While the Halcro has served me well, I heard new levels of clarity, dynamics, and silence with the M27.
I moved on to the Crime of the Century CD by Supertramp and listened to the song "School." This track is dramatic, with abrupt changes in pace that became more obvious with the M27. Instruments were well placed; imaging was excellent from side to side and front to back.
Elton John's "Candle in the Wind" possessed the same three-dimensional quality I had heard with my prior setup. What I did notice was an improved midbass presence that was natural and appealing.
With movies, I started with the Transformers: Age of Extinction Blu-ray disc. As with many action movies, the soundtrack was riddled with diverse levels of volume, which the NAD executed with immediacy. With the pod race from Star Wars--Episode I, the M27 exhibited excellent surround sound performance and maintained that center image in the rear of my room. It was completely engulfing, drawing me into the story and allowing me to forget about my assignment.
With The Bourne Identity on Blu-ray, during the apartment fight sequence, the M27 did a better job of discerning subtle creaks and squeaks just before an assassin swings in through a crumbling glass window. I believe the difference was the lower noise of the M27, along with the ability to rise to the occasion when needed. Overall, I believe the M27 performed better, even if the differences were small. I will say that I noticed a more drastic improvement when I implemented the M17 processor in lieu of the Onkyo. Moving from the Halcro to the NAD was an improvement to a lesser degree.
• The M27's casework, design, and construction are stunning--a perfect match for the new NAD Master Series M17 processor.
• The sound is clear and concise, yet warm and realistic along the entire frequency range--which was especially noticeable in the upper frequency range, such as cymbals, bells, and strings.
• The M27 exhibited a dead silent background, which created additional realism in music and movies.
• The M27 is compact in dimension and, more importantly, substantially less weight than alternative amplifiers.
• The M27 is so articulate that mediocre recordings may show their flaws.
• With an amplifier that is so resolving, it may reveal any weak links that exist in your system.
Comparison and Competition
To provide some perspective, I originally had an Earthquake Cineova Grande seven-channel amplifier powering my system. Its dimensions were 9.25 inches high, 18 inches wide, and 21 inches deep, with a weight of 122 pounds and similar power specifications as the Halcro MC70. The Halcro's dimensions are more compact in all directions, and it weighs significantly less at 55 pounds. While both of these amplifiers could play loud and did not display any indication of distortion, the Halcro had an advantage in being more musical, with more finesse and clarity. The NAD M27 is even more compact than the Halcro and 24 pounds lighter (31 pounds total), and it continues the trend of improved fidelity.
The power efficiency of an amplifier is as important to me as the gas mileage on a Ferrari--i.e., it's typically not a consideration. (I don't own a Ferrari; but, if I did, gas mileage would be the last thing on my mind.) High performance always trumps. However, if a manufacturer can provide both improved mileage and better performance, it definitely gets my attention. More important to me are the weight and dimensions of an amplifier. The Earthquake was a real inconvenience when it came time to find a suitable audio cabinet to hold it. I was relieved when I switched to the Halcro. Now the M27 fits my cabinet even better. While these issues are not the most important to consider when choosing an amplifier, you may want to give them some attention if the smaller and lighter amplifier delivers the goods.
Anthem offers a five-plus-two-channel amplifier combination, models A5 and A2, that would set you back $6,500 for the set, not to mention their much larger footprint and weight. Classe offers the same configuration with its CA-5300 and CA-2300, but its price point is even further out at $17,000 for the pair. The Marantz MM8077, reviewed here, appears as a bargain at $2,399 and is a single-box seven-channel solution. While it is hard to fathom the Marantz performing at the NAD's level, given what I heard, you may want to give it a look. The Krell Chorus 7200 is a seven-channel amplifier that claims Class A performance without the inefficiency, due to Krell's iBias technology, which sounds promising. However, at $9,500, the Chorus 7200 is over twice the price of the NAD, and I am not sure it would provide over twice the satisfaction.
The NAD M27 is a very compelling seven-channel amplifier due to its exceptional sound performance, high efficiency, compact size, and rich casework. Combining all these attributes at a price point that is below relevant competing amplifiers compels me to give this amplifier my highest recommendation. I believe this amplifier sets a new standard of performance and price. The M27 is an obvious mate when purchasing the M17 AV processor; however, the M27 is so stunning that I would recommend it as a separate purchase to mate with your existing processor, if you are in need.
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