NAD M33 integrated streaming amplifier
+ An amazingly versatile and well-specified digital streamer/amplifier that sounds great; cutting-edge amplification technology; room for future upgrades.
– This comes at a price.
Sound: 8.5/10
Value: 8/10
A guide to the ratings
TREPIDATION was the feeling that I had when asked to review the NAD M33 Streamer Amplifier. My last encounter with NAD was the industrial looking grey boxes that always punched above their weight in terms of performance to dollar ratio. No frills but good value for money, this has become the hallmark of the brand since the 1980s.
So when I found out that the NAD M33 sits at the top of the Masters Series with a price tag of a shade below RM26,000, I had reason to feel nervous.
To add to the price tag, the M33 is also a pure Class D amplifier. Class D? Aren’t they usually used for cars and cheaper amplifiers? Trepidation.

No holding back on specs
The M33 came in a big heavy box, with the unit wrapped in a velvety cloth bag. The amp itself was not as heavy as I thought it would be. It had a nice aluminium finish, with a square NAD logo and a large touch screen on the fascia.
The light weight is due to the Class D amplification which does not require heavy and bulky transformers. On the amplification itself, this is not your normal off-the-shelf Class D stuff, this amplifier utilises the HybridDigital Purifi Eigentakt amplifier technology. Proper cutting-edge amplification technology.
The M33 comes with individual isolation feet, which is good. There is also a big and chunky remote-control unit in the box, together with the power cables, a USB or 3.5mm input plug and an external microphone with a thin manual.
According to the specification sheet, this is a BluOS streaming amplifier with a continuous power output of 200 watts per channel into 8/4 ohms. BluOS is the same software that operates the Bluesound series of streamers. Not surprising, since NAD and Bluesound are both owned by the Lenbrook Group of Companies based in Canada. With BluOS, the M33 can also be configured for a multi-room set-up.
Built in is a 32-bit/384kHz ESS Sabre DAC and the software side is powered by a 1GHz ARM Cortex A9 Processor. It supports Airplay2, Alexa, Google Assistant and Siri, WiFi 5 and Qualcomm aptX HD Bluetooth. In terms of inputs, you get two coaxial digital, two Toslink optical, AES/EBU XLR, HDMI eARC, USB Type-A, phono MM and a pair each of balanced XLR and line. There also a pair of subwoofer outputs and preamp outs. A gigabit ethernet port allowed wired connection. And yes, there’s a high-current headphone output.
With a view on future needs, the M33 has MDC Slots for expansion cards should there be a change in technology. Phew!

In other words, the M33 has all the inputs that you will ever need or want from an amplifier plus the ability to upgrade. If one were to nit-pick… you cannot connect the streamer to an external DAC but that would be superfluous. Everything is integrated on this neat box. If you are the sort who enjoys adding black or silver boxes to your amplifier, then you may want to look elsewhere. The M33 looks pretty and elegant in a swanky living room by itself. As the title says, you just have to add speakers. No messy wires, no messy extension cords.
And the cherry on top, even after you add the speakers and feel that it does not sound as good as it did in the showroom, worry not. The M33 comes with Dirac Live Room Correction, which adjusts for frequency response and optimises the impulse response to match the room, to ensure that the whole system is calibrated for optimum performance.

LISTENING
On powering up via the touch button on top of the unit, the LED changes from red to white with the crisp screen lit up. Initial set-up via the BluOS app is easy with the app immediately finding the M33. The app can link with Tidal, Spotify, Qobuz, Deezer and Amazon HD, to name a few. It also has Tunein for online radio and the unique MQA version of Radio Paradise. By the way, the M33 natively unfolds MQA files. The big display shows what is playing when using one of the streaming services. The display turns to a huge VU meter when using other sources.
Now to the all-important sound quality. This is where the trepidation turned to pleasant surprise. The M33 is bold and ballsy with a nice bite at the high frequencies. Yet, at the same time, it carries a level of warmness in the midrange that I did not expect. The opening bars of Again by Black Stone Cherry (The Human Condition, 2020) retained the rawness of the electric guitars with the bass drum thumping away with a weighty slam. Excellent control at high volumes, never sounding tinny or harsh. I had to sit up. The M33 can rock. Slow and woolly this amplifier is not.
It can handle any genre thrown at it. With vocals, the M33 conveyed the sweet, smooth and bluesy voice of Rachel Price from Lake Street Dive in the MQA recording of Hypothetical from the latest album Obviously. This was done without losing the foot-tapping fun nature of the track, and at the same time, painting a nice room-filling soundstage. Detail is also very good but not at the expense of being too analytical and “hi-fi”. Instead, there is a naturalness in the sound which makes the M33 a good and pleasing all-rounder.

The M33 also has a decent MM phono stage but unlike conventional amplifiers, the it digitises its analogue inputs. It makes analogue become digital. Would it rob vinyl from what makes vinyl special? Again, trepidation.
Well, I am happy to state that the phono stage is decent. The airiness of Romeo and Juliet from Dire Straits’ Alchemy Live album was there, so was the rich whispery voice of Mark Knopfler. The intimacy and warmness were retained without much harshness. Perhaps this was due to the overall tonal quality of the amplifier. Despite the analogue signal from the turntable getting converted to digital and processed by the ESS Sabre chip, it did not sound too “digital”.
After about a week of listening, I started the Dirac Live process to see how the software configured the sound of my Buchardt S400 speakers. I have to admit that it was not for me. There was heightened headroom and a bigger soundstage with a more prominent spotlight on the performer. However, I felt that there was a sense of artificialness to the sound as a whole. I much preferred the sound with Dirac off. I am sure with more tweaking this can be improved further. It’s, however, something to keep the tweakers amongst us busy.

CONCLUSION
The M33 is a cutting-edge one-size-fits-all amplifier, a one-box heart of your music system. Even the remote control is somewhat superfluous with all controls being accessed via the excellent BlueOS app. I cannot heap enough praise at how well designed this app is.
At a glance, the NAD M33 may be expensive, but it will provide hours of musical enjoyment. When you look at it closer and take into account the excellent musicality, the innovation thrown in, the flexibility via Dirac and the level of future proofing, it is hard to say that it is overpriced. For me, I will no longer have any trepidation when faced with NAD’s high-end digital amplifiers!
Gear
Sources: Michel Gyrodec/Origin Live/Nagaoka MP300 for vinyl, Quad CD66 CD player, Surface Laptop via Roon with Denafrips Pontus 2 DAC / Amplification: Accuphase E470, Aimee SE-P3 Phono / Speakers: Buchardt S400, Harbeth Compact 7es2, Harbeth P3-esr/ Assorted cables including Quad Flat Copper Cable, QED One, Van Damme XLR
Price: £,3999 / $4,999
Malaysian price: RM25,999
Review sample courtesy of STARS PICKER AUDIO LIBRARY (+603-6156 1984) / Find your distributor.
You mention the Accuphase E-470 in the gear overview. How would you compare the M33 to the E-470 soundwise?