Today, I’ll be checking out NAD’s flagship surround sound preamp processor, the M17 V2. It’s an update to the venerable M17 that I reviewed back in 2014.

NAD M17 V2 Surround Sound Preamp Processor

Utilizing a unique card-cage design, it has been upgraded to the latest HDMI 2.0 interface along with the addition of Dolby Atoms processing into 11.1 channels. It also sports the full version of Dirac Live room correction with its automated frequency and phase adjustments. I’ve experienced Dirac in NAD’s T 758 and T 777 receivers and am looking forward to trying it again with the M17 V2. They have never failed to impress me with their sound quality and the Masters Series represents the very best NAD has to offer. When you see a model number beginning with the letter M, you know you’re about to listen to something very special.

Highlights

NAD M17 V2 Surround Sound Preamp Processor

  • 11.1 balanced outputs
  • Five HDMI 2.0 inputs with two HDMI outputs
  • Dolby Atmos processing
  • Dirac Live (full version) included
  • Four card cages for future hardware updates
  • BluOS streaming built in
  • Front-panel touchscreen
  • Premium build quality
Introduction

I have long maintained that the ultimate home theater sound comes from separates. There are several extremely-capable receivers available today but none of them can deliver the impact of a good processor and power amplifier combination. I’ve used such a system for the past nine years and there is nothing that would compel me to go back to a one-box solution.

In 2014, I had an opportunity to review NAD’s flagship combo, the M17 processor and M27 power amp. I found they provided fantastic sound quality and phenomenal detail with both music and movies. But high-end processors are often slow to catch up to the never-ending parade of new technologies. Jokes about receivers being obsolete by the time you get them home are getting old. In reality, a good processor can last for many years. Witness – I am still using an Integra DHC-80.1 from 2010. As long as I can continue to buy disc players with separate HDMI audio and video outputs, I have no plans to replace it.

That being said, I’ve recently experienced Dirac Live room correction and Dolby Atmos in my home theater, and yes, it has me thinking. NAD has leveraged its Modular Design Construction technology and added new hardware to the M17. The M17 V2 Surround Sound Preamp Processor brings HDMI 2.0, Dirac, and Dolby Atmos to a design that is already at the zenith of quality. They didn’t mess with what works, NAD simply added in a few new ingredients without spoiling the sauce. Let’s take a look.

NAD PREAMP PROCESSOR SPECIFICATIONS

11.1-channel Preamp Processor
Input Impedance (R and C):

56kΩ + 220pF

Input Sensitivity:

40mV (ref. 500mV out)

Maximum Input Signal:

>8Vrms

Signal/Noise Ratio, A-weighted:

>90dB (500mV in, 500mV out, volume set to unity gain), >80dB (2V out, volume maximum)

Channel Separation:

>70dB (ref. 1kHz / 10kHz)

Frequency Response:

±0.3dB (20Hz-20kHz, Tone Active), ±0.3dB (20Hz-20kHz, Tone Defeat)

Frequency Response (subwoofer out):

10-200Hz (-3dB)

XLR output:

>2Vrms

Maximum output level:

>8Vrms into 600Ω

THD (CCIF IMD, DIM 100):

<0.005% (20Hz-20kHz, 2V out)

Video Inputs:

5 x HDMI 2.0, 3 x composite, 2 x component

Video Outputs:

2 x HDMI 2.0, 3 x composite, 1 x component

Audio Inputs:

2 x coax digital, 2 x optical digital, 7 x stereo RCA

Audio Outputs:

11.1 balanced, 7.2 unbalanced, 3 x stereo RCA

Control:

1 x RS-232, IR – 1 x in, 4 x out; 12v trigger – 1 x in, 3 x out

Network:

1 x RJ45, 1 x USB

Dimensions:

17.1” x 6.1” x 15.2” (WxHxD)

Weight:

38.6lbs

Warranty:

Two years

Price:

$5999

Company:

NAD

SECRETS Tags:

nad, m17 v2, surround processor, preamp processor, surround sound, preamp, processor, dolby atmos, home theater, separates, Surround Processor Review 2018

Linkbacks

NAD T 777 V3 AV SURROUND SOUND RECEIVER REVIEW
NAD T 758 V3 AV SURROUND SOUND RECEIVER REVIEW
NAD M17 & M27 MASTERS SERIES SURROUND SEPARATES REVIEW

Design

NAD M17 V2 Surround Sound Preamp Processor Rear Panel

The M17 V2 is a fully-balanced design with 11.1 output channels. The rear panel is beautifully organized into distinct sections. At the top are the eight main channels, 7.1 if you will. The additional four outputs, representing four height channels, are included on an MDC card along with four digital inputs, two coax and two optical. Another card offers a bevy of analog video jacks. There are three composite inputs and three outputs, and I must say, it’s been awhile since I saw those familiar yellow connectors. You also get two, three-wire component inputs along with two outputs. This is something that is quickly disappearing from other receiver and processor brands. A third card contains all the stereo analog jacks, seven inputs and three outputs. The final card sports five HDMI inputs plus two outputs. It also has RJ45 and USB ports for networking, along with the silicon for Dirac Live and BluOS. The latter is supported via wired or wireless connection using a small dongle that plugs into the USB port.

NAD M17 V2 Surround Sound Preamp Processor MDC Cards

All those connectors are of little value unless there is technology to back them up. The M17 V2 serves up a large helping that includes Dolby Atmos and the full version of Dirac Live room correction. With 11.1 output channels, a 7.1.4 system is possible. 5.1.4 is more common and I went barebones for this review with 5.1.2 using a pair of PSB XA Atmos modules placed atop my main tower speakers.

The full Dirac software offers quite a few more options than the Dirac LE that ships with the T 758 and T 777 receivers. The big one is the ability to correct frequency response over the entire 20Hz-20kHz range. Dirac LE only corrects from 20-500Hz. You also get two additional room layouts from which to plan mic placements. The accuracy of any room correction utility is largely dependent on the number of measurements and their locations. Dirac Full adds Chair and Auditorium to the Sofa layout included with LE. It also adds a second license, so you can run it from two different computers.

Physically, the M17 V2 is high-end all the way. From the moment you start unpacking, you know this isn’t your average mass-produced electronics component. My sample arrived double-boxed and opening it brought back the same feelings I had as a child, opening presents on Christmas morning. After lifting out a molded cardboard top protector, I was greeted by the processor, neatly snuggled in a large drawstring bag, and two small boxes with ancillary components. There isn’t a crumb of Styrofoam in sight, and for that, I applaud NAD. All packaging should be like this.

Four magnetic feet attach to integrated spikes on the chassis’ bottom. You can leave them off if your rack allows but they will mar wood surfaces. I used the feet which have thick rubber coatings underneath. The front shows just a small NAD logo, ringed by light when powered, a large center touchscreen, and a volume dial that moves with silky smoothness. On the top edge is a tiny touchpad that serves as the power button. My only nitpick is that the dimmest setting of the touchscreen is still too bright in my completely-dark room. The top panel features large ventilation grills though the M17 V2 doesn’t radiate too much heat. Still, it’s best give them ample clearance.

NAD M17 V2 Surround Sound Preamp Processor Remote

The remote is the same large and heavy aluminum wand I remembered from the last M17 I reviewed. It’s a substantial piece that only has one flaw, several sharp corners. The aluminum is machined but its edges are not rounded. It would not be difficult to cut oneself. It is backlit in a soft blue that activates when a button is pressed. I thought at first it wasn’t motion-sensitive but a few instructions from NAD showed the appropriate button combination to activate the feature. The handset can be programmed to operate other components in a multi-mode configuration, much like the remotes that come with high-end receivers.

Set Up

Performing a proper installation of a product like the M17 V2 requires a bit of planning. Configuration starts with a good deal of wiring, then a trip through the processor’s menu, and finally, Dirac Live setup. My system is anchored by Emotiva power amplifiers, an XPA-5 and an XPA-2. I wired the M17 V2’s balanced outputs directly to them using Blue Jeans XLR cables. For the height channels, outputs come in the form of mini-DIN connectors which I had not seen before. NAD thoughtfully provides four adaptors, so you can plug in standard sized cables. I wired them to a pair of PSB Imagine XA Atmos modules placed on top my Axiom LFR-1100 towers. For this review, I only ran the front baffles, effectively turning them into M100s. The center was a VP180 and the surrounds were QS8v3. The sub was an EP800, also connected via XLR.

After confirming operation with test tones, I turned to Dirac Live setup. The first task was to update the processor’s firmware and BluOS. NAD includes a Wi-Fi module to plug in the USB port, but I opted to use the RJ45 jack for a direct connection to my home network. The update took only a few minutes. Then, I added the M17 V2 as a BluOS player in the iPhone app. It allows access to vast amounts of streamed content from carriers like iHeart Radio and Spotify.

I’ve already detailed the running of Dirac Live in my previous reviews of the T 758 and T 777 receivers, so I won’t rehash it here. I was anxious to try the additional features of the full version though. The extra room layouts are intriguing because my theater doesn’t really resemble a sofa configuration. Chair is closer to my actual seating arrangement. And I wanted to hear the effect of correction at frequencies higher than 500Hz.

It was quite interesting to measure nine points within the four square-feet that constitute my theater recliner seat. The layout is shown graphically in the Dirac interface and requires two different heights to work its magic. It’s important to get the channel levels dialed in before starting the measurements runs because if any clipping occurs, you have to start over. The screen preceding the measurements sends a sweep to each channel, so you can tweak them first.

NAD M17 V2 Surround Sound Preamp Processor Frequency Correction

NAD M17 V2 Surround Sound Preamp Processor Impulse Response Correction

Above are the plots from my front two speakers. The baseline measurement is gray while the correction is shown in green. You can see how Dirac flattened out the frequency response with a gradual roll-off towards the high end. And impulse response is now neutral throughout. The full version also defaults to correcting the entire frequency range which I found to be a distinct advantage. It creates a beautifully layered sound that makes individual elements easier to hear which maintaining an ideal balance. That, coupled with the impulse response correction makes for a far more cohesive sound field than I ever experienced with Audyssey or with no correction applied.

In Use
Movie Watching

NAD M17 V2 Surround Sound Preamp Processor Movies

A surround processor is principally a machine for playing movies and that’s where I concentrated my listening sessions. Dolby Atmos not only adds the additional dimension of height to the sound field, discs mixed with the object-oriented format have more presence and impact, even when played through a traditional 5.1 setup. Scalability is the key. Your processor or receiver takes the speaker layout into consideration and adapts the audio to sound its best with the speakers you actually have installed. There will never be missing information or effects that aren’t fully realized. So, I gave up little or no quality by simply adding two PSB Imagine XA height modules to my front tower speakers.

From the first action scene in Kong, where hapless pilots insist on flying their helicopters close to a giant gorilla rather than simply gaining a bit of altitude (but then we wouldn’t have a movie, would we?), the amazing control exerted by Dirac over my EP800 subwoofer was apparent. The room literally shook, yet I could hear every frequency and every nuance. I’ve never heard such loud bass that was also clean and detailed. There’s always a point where it turns to mush but the M17 and Dirac let me drive that sub to ear-bleeding levels. Mid and high range details were equally clean and well-rendered. The presentation brought the word “layers” to mind. Each facet of the action, thumping helicopter blades, screaming humans, roaring animals, rustling trees, was perfectly separated from the rest, yet integrated at the same time. It’s hard to find a single word to describe it but I know I liked it.

Ghost in the Shell, has plenty of subtle details hidden among some intense and loud moments. It’s full of spatial cues and ambient effects in the surround channels. Dolby Atmos provided a great sense of the vertical here, along with a tremendously-wide front sound stage. Through all those effect layers, dialog never wavered in its clarity. Even the quietest mumbling was easy to discern.

With the advent of Blu-ray came uncompressed sound, and we are now all spoiled because of it. Listening to straight Dolby Digital or DTS has become a chore because it sounds so harsh and undefined. Imagine my surprise when I dropped in The Blues Brothers and listened to a few musical numbers. I was sure I was hearing DTS-HD Master Audio but a quick check of the info screen confirmed I wasn’t. If you are looking for a way to revitalize old DVDs and early Blu-rays that don’t have lossless sound, the M17 can make that happen. I’ve never heard this movie sound better. Music, dialog, primitive effects, they all came across with a modern aesthetic rather than that familiar Eighties vibe.

Music Listening

NAD M17 V2 Surround Sound Preamp Processor Music

Of course, NAD was around long before home theater became a thing, and their dedication to music has never wavered during that time. The M17 is every bit a high-end audio component, capable of bringing out the finest detail in any recording. With that in mind, I spent several hours listening to two-channel CDs.

Before heading for some classical stalwarts, I went for the latest from Five Finger Death Punch, and Justice For None. Needless to say, that bass slam was a major factor. I’m more accustomed to the way it sounds in my car, so it’s no surprise that the M17 found a whole lot more detail. Metal often sounds like mush on the best systems but here, Dirac and NAD’s unfailing devotion to detail brought out every layer, every effect, and every instrument. And volume? There was no limit to how high I could go. I expected the neighbors to call the cops at any moment. I have to give some credit to my Emotiva amp but the M17 is the absolute king of resolution and dynamic range.

Those video metaphors continued as I dialed it down with Strauss’ Death and Transfiguration in a live performance by the New York Philharmonic. The sound stage was both broad and deep as I was transported to the best seat in Avery Fisher Hall. Even with the recording’s background noise, no pianissimo was left behind. Listening to the M17 is like watching a premium plasma or OLED TV. That contrast really helps every detail pop.

I spent the rest of my time working through Francisco Mignone’s Sixteen Waltzes for Solo Bassoon played by New York bassoonist, Frank Morelli. His sound is quite expansive, made even more so by a reverberant hall. It was a pleasure to crank the volume to where I felt as though I were sitting on stage right next to him. I couldn’t help but break out my copy of the music and make a few performance notes. Listening to solo instruments this way really satisfies my curiosity and wish to understand the process. The M17 is not only a great-sounding preamp, it serves as a professional reference tool.

At no time was I tempted to try the surround modes with two-channel music. The sound is so broad and deep, there is no need for them. Many multi-channel processors focus on surround sound and put their two-channel chops lower on the priority list. NAD does not. The M17 V2 is a premium audio component no matter how many speakers you have.

Conclusions

NAD M17 V2 Surround Sound Preamp Processor

At $5999, the NAD M17 V2 SURROUND SOUND PREAMP PROCESSOR is expensive, but I defy any preamp to best it for less than twice the price.

Likes
  • Unfailingly accurate and detailed sound
  • Premium build quality
  • Dirac Live
  • HDMI 2.0
  • Dolby Atmos
Would Like To See
  • Stereo subwoofer outputs

Though I write many projector reviews, I know that the most important component in any successful home theater is the audio system. The world’s greatest display becomes meaningless if it isn’t backed by good sound. The NAD M17 V2 Surround Sound Preamp Processor, does that and more. My experience with NAD told me to expect excellent detail, broad dynamic range, and a neutral presentation. But with the addition of Dirac Live, this processor takes things to a whole new level.

Like any room correction system, Dirac requires a bit of fiddling to get right. I spent some quality time with the software and my efforts were rewarded with incredible balance, clean sound at high volumes, and a system that was equally at home playing Hollywood blockbusters and the finest music.

My complaints are less than minor. Stereo subs would be nice though from my perspective, I don’t have a large enough room to benefit from them. And the remote, though extremely competent and beautifully made, would benefit from a little machining to remove those sharp corners.

These are not things that would give me even a moment’s pause. The M17 V2 is not inexpensive but I think it’s worth every penny. Had I the funds, it would not leave my theater. It is truly a reference-level product and with support for HDMI 2.0 and Dirac Live room correction, it appears ready for the future. It requires an investment of both money and time, but I promise you, the results are worth it. It doesn’t just deliver great sound, it provides a great experience. The NAD M17 V2 Surround Sound Preamp Processor receives my highest recommendation.