Nad M2 owners Manual

Masters Series M2

Direct Digital Amplier

The World’s Most Advanced Direct Digital Amplier

The NAD M2 Direct Digital Amplier represents a new level of amplier performance. Combining the ultra low distortion

and noise levels of the nest linear Class A and Class AB ampliers with the efciency and streamlined signal path of

the digital amplier, the M2 is the rst implementation of a new amplier technology called Direct Digital Feedback.

Co-developed with UK based Diodes Zetex Semiconductor, and using a unique implementation of their patented DDFA

architecture, the M2 redenes what is possible with digital amplier technology.

The M2 Direct Digital Amplier represents the culmination of a decade long NAD research project, capped by three

years of intense development. The result fully justies the investment. We believe that the M2 sets new benchmarks for

both measured performance and subjective musical quality.

Features

> Blinding Speed and Precision

Extremely wide 35-bit data path for Direct Digital

Feedback compensates without truncating any

> Stunning Intimacy with the Music

Directly accepting a digital PCM input completely

eliminates the noise and distortion added by cascaded

information in the original signal. Running from a master

clock frequency of 108MHz there is enough speed to

keep a very wide amplier bandwidth and very low noise

and distortion in the audio band.

analogue amplifying stages, as found in traditional Class

AB or even Class D ampliers. Streamlining the signal

path by eliminating several amplier stages provides a

feeling of being that much closer to the performers.

> see Features continued

Features continued

> Advanced Power Supplies

The M2 uses three power supplies, all of them highly

efcient switch mode types. Each channel gets its own

high current power supply in a dual mono conguration.

The Input stage and control sections get their own

dedicated supply with multiple regulated secondary

voltages for individual sections.

> Analogue Input Section

We have provided a state-of-the-art Analogue-to-Digital

converter stage for analogue sources and for those who

still choose to use a traditional analogue preamplier.

This fully balanced stage accepts both a Single Ended

input and a Balanced XLR input. Both the analogue

input buffer amp and the ADC are of the highest quality

available today.

> Dynamic Power

Digital PowerDrive optimizes performance when driving

real loudspeakers by maintaining optimum power

delivery and lowest possible distortion. Unlike most

digital ampliers that do not have power reserves, the

M2 has excellent dynamic power capabilities.

> Digital Processor Loop

This unique feature allows the advanced user to insert

external digital lters into the signal path. The Optical

TosLink format allows fuss-free connection to Macs

where there is a wide library of crossover lters and

room correction programs. Digital outputs in both coaxial

and optical formats allow for multiple M2s for bi- or

tri-amplication of advanced loudspeaker systems.

> Effective Control

> Digital Soft Clipping

Digital Soft Clipping prevents the harsh sound and

potential speaker damage that can result with a severely

overdriven amplier.

An RS-232 serial interface is exible for home

and studio use, allowing the M2 to be controlled

from the PC or via advanced control systems like

Crestron and AMX.

Direct Digital Explained

A true digital amplier can be thought of as a Digital-to-Analogue Converter that directly drives the loudspeaker.

This describes the M2 perfectly, except to say that the M2 actually has the same level of precision as the very best low

level DACs! This technology is far more sophisticated than the Class D analogue ampliers that are often erroneously

referred to as ‘digital’ ampliers.

This level of performance is unprecedented and is made possible by application of Direct Digital Feedback.

The idea of a closed loop digital amplier is not new, but the NAD M2 is the rst practical implementation of the concept.

Feedback Reinvented

The concept of feedback is simple yet brilliant. Compare the signal at the output of the amplier with the signal at the

input; any difference is caused by the distortion of the amplier. Now, invert that difference signal and add it to the

incoming signal and the difference signal will offset and cancel out the distortion. This is how it’s done in conventional

linear ampliers.