NAD Masters Series M12 Digital Preamp DAC and M22 Stereo Amplifier

Sensible but Serious

Equipment report
Solid-state power amplifiers,
Solid-state preamplifiers,
Digital-to-analog converters
NAD M12,
NAD Masters Series M12 Digital Preamp DAC and M22 Stereo Amplifier

NAD electronics has been marching down audio’s red carpet for years, picking up awards and accolades from high-end journalists and customers alike. Its classic BEE line—all buttons and knobs, and blue collar to the core—is still being turned out in sturdy but sensible, olive-gray stamped enclosures. Outward frills are kept to a minimum, and that’s always been NAD’s point. It’s the sonic thrills rather than the visual bells and whistles that customers have come to expect, and that keep them coming back.

The Masters Series represents the more uptown side of NAD. Stylish and sophisticated, this is a company flexing its technical muscles while preserving the underlying value it is famous for.

In case your experience with NAD electronics ended with the original, circa-1978 3020—the modest integrated amp that addicted many a young audiophile to this hobby—you’ll be in for a big surprise. The latest generation Masters Series (the originals were introduced in 2005), as embodied in the M12/22, is unreservedly gorgeous. The aluminum casework is elegantly crafted. Its shiny black, accented front panel and vented top plate are sumptuous to the eye and the touch. Both units are powered-up via a recessed top-mounted switch. The M12’s large, readable touchscreen display easily handles functions normally left to a small army of buttons and toggles. The only vestige of a bygone era is the nicely weighted rotary volume knob. For that, let us all give thanks.

The M12 is a preamplifier/DAC—a high-end segment that has been growing in leaps and bounds. Like the M2 Direct Digital Amplifier, and more recently the C 390DD, the M12 employs its own “Direct Digital” 35-bit processing technology, thereby circumventing all analog stages in the signal path. Music remains in the digital domain through the preamp. By NAD’s reckoning this eliminates the phase shift, noise, and distortion of many analog designs.

Before I describe back-panel connectivity, a word or two is needed about a unique feature of the M12 architecture. NAD calls it “Modular Design Construction” or MDC, and it looms large in the Masters Series. MDC uses replaceable cards that fit into slots on the M12’s back panel, essentially making the unit future-proof as upgraded features become available. The M12 back panel has slots for three additional modules. Currently one such MDC option is the DD HDM-1 HDMI module with three inputs and one output (3D video pass-through). My M12 review sample, however, was outfitted with the optional DD BluOS network-audio module, which permits streaming of various music services like Tidal and TuneIn radio, plus high-resolution PCM files (no DSD yet) from a NAS device or local USB HDD/SSD. The NAD Controller App (from the iTunes App Store) manages a music library and can be controlled with an iOS or Android device. The card includes integrated WiFi/Ethernet and aptX Bluetooth connections for hi-res streaming from a smartphone or tablet. For Millennials this module is likely a must.

Even without the DD BluOS module, standard M12 connectivity is excellent. The back panel is densely populated with inputs, including AES/EBU, asynchronous 24-bit/192kHz USB Type B, coaxial digital, and optical digital, along with balanced and single-ended line-level. There are also front and rear USB-A inputs capable of 24-bit/48kHz resolution. Additionally there’s a pure Class A buffer using the newest generation of “Super OP Amps” to provide low-impedance balanced and single-ended connections to power amplifiers or active loudspeakers. Also resident is an mc/mm phonostage module with settings for both moving-magnet (mm) and moving-coil (mc) cartridges. Gain is set automatically. Vinyl lovers should keep in mind that with Direct Digital processing a 24/192 ADC will convert the analog signal to digital, automatically setting the gain for the best resolution and lowest noise. The included remote control handles all functions quite capably.

Master Stroke
NAD describes the M22 as a hybrid digital amplifier. Output is rated at 250Wpc into 8 ohms, and >650W into 2 ohms. In NAD’s words, the M22 “uses the latest nCore amp technology licensed from Hypex.” Further refinement of the UcD concept (Bruno Putzeys was its inventor) has yielded distortion that in NAD’s words is now “below measurement, [providing] an ultra-high damping factor and unconditional stability with any speaker.” Additionally, the M22 is DC coupled throughout, from input to output. There is no capacitor in the signal path. The power supply is a custom switch-mode design, while secondary supplies are individually regulated and decoupled at each op-amp to maximize dynamic range and lower noise. The M22 employs NAD’s latest generation of digital Power Drive, which automatically senses the speaker’s impedance and adjusts and controls the amp’s power envelope to more efficiently drive that particular load.