The NAD C 390DD is not only a new concept in amplification, but also in audio
system architecture. First introduced in the now famous NAD M2 Direct Digital
Amplifier, Direct Digital technology has been praised for its transparent,
dynamic and detailed sound quality. Like the M2, the C 390DD has no analogue
stages in the signal path, keeping music in the digital domain right up to the
speaker outputs. All preamp functions are executed in the digital domain without
the phase shift, noise and distortion that plagues all analogue designs
regardless of price or pedigree. Its 35-bit architecture and 108MHz master clock
also make Direct Digital one of the most accurate DAC technologies
available.
Modular Design Construction
The advantages of a pure digital system are many, but one drawback is the
constantly changing delivery formats for digital content. Each of these formats
typically requires specialized hardware and software, often with licensed IP and
content copy protection.
For this reason, we place all digital interface circuitry on easily
upgradable modules. We call this Modular Design Construction or MDC. The C 390DD
comes standard with one module, the DD USB 1 for USB interface, and open slots
for two more modules. Optional MDC modules currently include the DD HDMI-1 HDMI
Module and the DD AP-1 Analogue Phono module. The DD HDMI-1 offers three HDMI
inputs and one output with video pass through. This opens up the possibility of
using the C 390DD as the heart of a "Video 2.0" system using the mandatory
two-channel linear PCM soundtrack from Blu-ray or DVD to make a compelling
two-channel high definition theatre presentation. Many Symphony Orchestras and
some specialty music labels are also released in HD recordings on Blu-ray or
DVD. The DD HDMI-1 is fully 3D video compatible, but there is no surround sound
decoding or video processing.
The DD AP-1 module is also very innovative, using super high quality
Analogue-to-Digital conversion to make analogue sources compatible with the C
390DD's pure digital circuitry. Using 24/192 processing, the ADC circuit
auto-ranges for the best possible resolution and lowest noise. The phono circuit
has impedance settings for both moving magnet (MM) and moving coil (MC)
cartridges with gain automatically set. For the first time, RIAA equalization is
performed completely in the digital domain using precision DSP filters. The
result is far more accurate than even precision analogue circuits and has the
additional benefit of eliminating phase shift from the circuit.
Power
The C 390DD has a very high continuous power rating of 150 watts per channel
with almost immeasurable distortion and noise. More importantly, thanks to NAD's
exclusive Digital PowerDrive circuit sensing the speaker load and altering
amplifier characteristics, power delivery into real loudspeakers is enhanced
with the most efficient power delivery and best safety margin. Resulting in
power output that can more than triple the rated power for short periods of time
to accurately and effortlessly reproduce musical transients. The result is that
the C 390DD sounds even more powerful than its already impressive continuous
power rating.
System Architecture
Since the C 390DD performs the functions of multiple conventional components,
not only is the sound improved, but the way a music system is configured can
change as well. The C 390DD is ready for the world of computer audio with its
asynchronous USB input that can directly stream 24/96 content from your PC, Mac
or network-attached storage device (NAS). USB memory sticks and hard drives are
also supported with both front and rear connections. Or add NAD's innovative C
446 Digital Media Tuner to stream and manage your internet radio and NAS devices
as well as local FM and AM broadcasts. Naturally, traditional components like
CD, DVD, and Blu-ray disc players can all be accommodated. Even older analogue
sources and turntables can be used with the optional DD Analogue/Phono
Module.
Exclusive Features
The Direct Digital platform includes a large amount of DSP processing power,
and NAD has fully exploited this power with a toolbox full of useful features.
Even familiar features, like the volume control, benefit from the Direct Digital
platform. Perfect signal tracking and channel balance combined with a total
freedom from noise and distortion characterize this remarkable volume control.
Traditional bass and treble controls also take on a new usefulness when
distortion and phase shift are totally absent.
An 'electronic crossover' function is also included to easily allow
bi-amplification or subwoofer integration. Frequencies from 40Hz to 200Hz can be
selected with the high pass signal sent to the C 390DD amplifier section and the
low pass sent to the preamp out.
One of the major problems in any high power music system is what we call
'room modes' or 'standing waves'. The wavelengths in the bass frequencies are so
large that room dimensions disturb the even propagation of the sound (think of
water ripples in a fish tank - when the wave hits the tank boundary a reverse
interference wave is produced). The result of this effect is that certain bass
notes are reinforced and become much too loud, making the bass sound 'boomy'.
This effect actually changes the perception of the harmonic structure of the
bass instruments and spoils the illusion of "listening through" to the acoustic
space of the recording. Our simple solution is what we call Room EQ. Playing
back a supplied test tone sequence allows this problem to be easily tamed using
your ears and the C 390DD Room EQ filters. There are six frequency centres in
the low bass region that can be cut (or slightly boosted) to remove the 'boom'
without reducing the low bass response. The width or "Q" of the filter can also
be adjusted to be wide or narrow to address a number of different room
configurations.
Software Defined Product
Not only is the hardware platform of the C 390DD flexible and upgradable, but
also almost every aspect of this fine instrument is software defined and can be
upgraded. Future MDC upgrade modules are in the works to add new features and
functions. Existing features can be upgraded with a simple software update. The
C 390DD comes standard with eight inputs, and with the optional MDC modules,
this can be expanded to 14! Inputs can be activated or hidden, and can be
renamed to reflect the specific source component attached. Listening Mode,
Polarity, and SoftClipping can all be easily selected and adjusted. RS-232, IR
Inputs/Outputs and 12V triggers all make integration with home automations
systems simple and effective.
The Future Begins Now
Small footprint, large power, low energy consumption, future-proof
upgradability, software defined operation, backward compatibility, easy
integration and a new high definition system architecture. All this and more is
combined with what is arguably the most accurate DAC/amplifier ever devised in
this radical yet, affordable package. Now is the time to update, upgrade and
upend your preconceived notions of what a music system looks and sounds
like.
