Direct Digital Technology: Direct Digital technology has been praised
for its transparent, dynamic, and detailed sound quality. The NAD C 390DD direct
digital integrated amplifier has no
analog 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.
Digital PowerDrive Circuit: The NAD C 390DD direct digital
integrated amplifier 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.
DSP (Digital Signal Processing): The Direct Digital platform includes
a large amount of DSP processing power. 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 integrated amp's volume control. Traditional bass & treble
controls are also improved, because distortion and phase shift are totally
Bi-Amplification: An electronic crossover function is 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. Many of today's
loudspeakers offer the option of Bi-wiring. This separates the HF crossover from
the LF crossover, and offers enhanced performance by preventing LF returned
currents from affecting the HF performance.
Room EQ: Room EQ is NAD's simple solution to problematic 'room
modes' or 'standing waves' that result in undesirable 'boomy' bass. 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 centers 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
- Frequency: There are six filters available in the frequency range
where standing waves typically are a problematical: 40Hz, 63Hz, 80Hz, 125Hz,
200Hz, and 250Hz
- Level: The 6 frequency centers in the low bass region can be cut
or slightly boosted to remove the 'boom' without reducing the low bass
response. Each filter can be boosted by up to 4dB or cut by up to 12dB in
2dB increments. The reason there is a smaller amount of boost than cut is
because boosting a null frequency actually increases the null making the
problem worse. Fortunately, the ear is less sensitive to sound missing than
it is to sound added. The objective is to tame the 'boom' in the bass,
resulting to a much more incisive and realistic sound.
- EQ: The width or 'Q' of the filter can also be adjusted to be
wide or narrow to address a number of different room configurations.
Digital Soft Clipping: NAD's proprietary Soft Clipping allows a graceful overload without the
usual generation of high-order harmonic distortion that normally occurs as the
sine wave gets squared off. Now digitally controlled, it can be carefully
modeled for ideal results. With Digital Soft Clipping turned 'On', it gently
limits the output of the C 390DD to minimize audible distortion should the
amplifier be overdriven. Soft Clipping may simply be left 'On' at all times to
reduce the likelihood of audible distortion from excessive volume settings. Set
to 'Off' for more critical listening and to preserve optimum dynamics.
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, NAD places all digital interface circuitry on easily upgradable modules.
NAD calls 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 Analog Phono module (both sold separately).
- DD HDMI-1 HDMI 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.
- DD AP-1 Analog Phono Module: The DD AP-1 module is also very
innovative, using super high quality Analog-to-Digital conversion to make
analog sources compatible with the C 390DD's pure digital circuitry. Using
24-bit/192kHz 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.
Remote Control: The included IR remote control handles the key
functions of the C 390DD. The IR remote can also be used to directly command
other NAD products that respond to applicable common remote control codes. This
includes other NAD Stereo Receiver, Integrated Amplifier, and Preamplifier
models. It has additional controls to remotely operate NAD CD Players, AM/FM
Tuners, and dedicated AM/FM/DB Tuners. It will operate up to a distance of 23'.
The remote requires two "AA" alkaline batteries (included).
Listening Modes: The C 390DD offers distinct listening modes, tailored
for different types of recording or program material. The following listening
modes can be selected.
- Stereo: Select the Stereo listening mode when you wish to listen
to a stereo production, such as music CD or FM broadcast.
- Mono: Use the Mono listening mode when the audio source format is
mono. The mono information is replicated on both left and right channels
- Reversed: The Reversed listening mode sends the right channel to the left speaker and the left
channel to the right speaker. This can easily correct a reversed input
connection or incorrectly recorded music source.
Tone Control: The NAD C 390DD direct digital integrated amplifier lets
you adjust Bass (+/-10 dB), Treble (+/- 10dB), and Balance (L10/R10) settings.
Polarity: This setting allows compensation for recordings that have
reversed polarity. You can choose between Positive or Reversed.
- Positive: A positive sine wave at the input remains positive at the
output. Polarity is defaulted to "Positive" setting.
- Reversed: A positive sine wave at the input is negative (inverted)
or reversed at the output.
Speaker Compensation: The digital impedance compensation filter allows
fine tuning of the top octave to match the speaker impedance (2 to 8-ohm). This
will result in perfectly flat frequency response at 20 kHz. The effect of this
filter may not be audible but it is measurable, and it compensates for the small
effect of the digital reconstruction filter that eliminates the 288 kHz sampling
frequency of the amplifier.
Renaming Source Inputs: A particular source input can be
renamed according to your preference. You can use up to 20 characters in
renaming a source input.
USB (Type-B) Port: The NAD C 390DD direct digital integrated amplifier is ready for the world of computer audio with
its rear-panel asynchronous USB (type-B) input that can directly stream 24-bit/96kHz content from your
Mac computer, or other network-attached storage device (NAS). Your
computer will need to meet the following system requirements.
- Windows PC Users: Microsoft Windows XP Service Pack 2 or higher,
Microsoft Windows 7.
- Mac Users: Minimum Mac OS X Snow Leopard (version 10.6) and later
Dual USB (Type-A) Ports: The NAD C 390DD integrated amplifier offers
dual USB (type-A) ports - one on the front-panel and one on the rear-panel. USB
(MSC) devices and hard drives with stored music can be connected for audio
playback. The following are the C 390DD's capabilities with respect to USB
- Supports playback of MP3, WMA, and FLAC files
- FAT12/16 root directory up to 256 files (short names)
- FAT12/16/32 up to 65,535 files (short names) per directory
- FAT file system limited to 2TB
- File and directory names limited to 64 characters
- Up to 16 maximum level of directories
- Supports USB version 1.1
Note: The integrated amp's USB ports are not compatible with Apple
iPod, iPhone, or iPad.
Digital Inputs: The NAD C 390DD features two rear-panel optical (toslink)
digital inputs and two coaxial (RCA) digital inputs to connect your digital
audio components. Connect your CD, DVD, and Blu-ray disc players. You can also
add NAD's innovative C 446 Digital Media Tuner (745C446, sold separately) to
stream and manage your internet radio and NAS devices, as well as local AM/FM
broadcasts. The Digital inputs support sampling rates of 32-192khz.
Digital Outputs: The C 390DD also features a rear-panel optical (toslink)
digital output and coaxial (RCA) digital output. This can be used to connect an
external digital processor, the Nuforce iCon external headphone amp (773ICNHDPB,
sold separately), or other outboard digital device.
Digital XLR Input: The NAD C 390DD is fitted with a Digital XLR jack
to connect high-end audio sources, such as SACD and DVD-Audio players.
Binding Post Speaker Output Terminals: The NAD C 390DD direct digital
integrated amplifier is equipped with two sets of speaker outputs (total of 8)
that are identical in function (parallel connection) and are provided for ease
of Bi-wiring your compatible loudspeakers. You can use bare wire (minimum of
16AWG), banana-type plugs (single only), and pin-connectors to connect your speaker wire to
the NAD C 390DD.
Note: The NAD C 390DD does not offer 'B' speaker terminals.
Pre-Out/Subwoofer Output: These two RCA outputs have dual
functionality. They can be used as a preamp output or a subwoofer output.
+12V Trigger Output/Input: The +12V trigger output (3.5mm) lets you
turn on/off another device along with the C 390DD. The integrate amp can
also be turned on/off by another device using the +12V trigger (3.5mm).
IR In: The 3.5mm IR input is used to control this unit using an
optional infrared repeater or the IR output of another component.
RS-232 Port: The rear-panel RS-232 port allows connection to a
compatible PC or external whole-house control system from companies such as AMX
or Crestron. NAD is a certified partner of AMX and Crestron and fully supports
these external devices.
AC Power Cord: The C 390DD comes supplied with a detachable 6' AC
Ground Terminal: The NAD C 390DD requires a grounded AC receptacle or
a separate earth ground