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NAD C 390DD
Direct Digital stereo integrated amplifier
Item # 745C390DD | MFR # C390DD
This item is no longer available.
Our take on the NAD C 390DD by Crutchfield's Woody Sherman
Purity in a box
It's almost a Zen thing — the pursuit of sound quality so authentic and uncolored that it's almost indistinguishable from sitting next to the performer, the recording engineer, or the sound mixer. NAD gets it. You want the scope and power of the original sound creator's intentions, without anything standing in the way. That's why the NAD C 390DD was built — to provide impeccable, powerful sound quality in the service of artistic vision.
It speaks digital
The C 390DD is built around NAD's innovative Direct Digtal amplifier technology. It reclocks and regulates incoming digital signals as needed. Once prepared at the input stage, all signals stay exclusively digital along its internal pathways, only becoming analog again in a digital-to-analog process just before the speaker terminals.
Your digital audio sources will be error- and jitter-free thanks to the C 390DD's internal 35-bit architecture and 108MHz master clock. The 3 asynchronous USB inputs (2 back, 1 front) decouple computer-originated files from locally originated timing errors and reclock those signals so that they conform to the C 390DD's internal framework. In the rear of the unit, one USB type B connector connects your computer, while the other two USB type A inputs support flash memory devices and external hard drives. These USB inputs can directly play 24-bit/96kHz content. There are 2 optical and 2 coaxial inputs to support disc players, DVRs and other media devices. And an AES/EBU XLR input accommodates pro digital components.
"With both of my sets of speakers, the C 390DD had me marveling at the stunning clarity of its reproduction across the audioband. That deep bass impact was accompanied by equal measures of detail and air, of the textures of bass-guitar strings and the sizes of recording spaces, the sound of felt-tipped hammers on piano strings. Listening to music through the NAD was a lot like seeing HDTV for the first time: a marvelous hearing of the familiar world through a pristine pair of new ears. I've written before about hearing "into" music, but, oh man, not like this."
Modules keep it versatile
The C 390DD can be made more versatile courtesy of NAD's Modular Design Construction (MDC) concept, whereby specialized plug-in input/output modules can be added as needed. Analog phono signals are welcomed by an optional DD-AP1 module, which seamlessly converts all the subtleties of your turntable's analog signal to a high-resolution digital stream. You can also host 3 HDMI inputs and 1 output with the optional DD-HDM-1 module, increasing its utility at the heart of your entertainment system. HD signals are cleanly passed through and noiselessly switched along the way to your monitor. The C 390DD comes standard with eight inputs, but you can expand the system to 14 inputs with the optional MDC modules. Inputs can be activated or hidden.
Finally, don't forget NAD's legendary pristine, exquisitely controlled management of power. The C 390DD's got a continuous power rating of 150 watts per channel, while exhibiting almost no distortion or noise. The Digital PowerDrive circuit senses speaker loads and alters the amplifier's power delivery to drive your speakers with maximum efficiency. Instantaneous bursts of more than twice the system's rated power will give you unparalleled nuances from your music. The C 390DD will be ready in an instant, the moment you need a fast transient, a slamming kick drum, or a flying violin bow.
" This combination of sound quality and features makes the C 390DD a very capable and compelling package. I can't think of another integrated amp anywhere near the C 390DD's price that I'd rather own.... The NAD C 390DD is an extremely sophisticated, forward-looking product whose feature set perfectly matches the needs of today's music listener."
— From Robert Harley's review in The Absolute Sound, July/August, 2012
What's in the Box:
- Direct digital integrated amplifier
- 6' AC power cord (with 3-prong North American plug)
- 6' AC power cord (with 2-prong European plug) IR remote control (AVR 4)
- 2 "AA" batteries
- Quick Start Guide
- Warranty Card
- 150 watts x 2 channels into 8 ohms (20-20,000 Hz) at 0.005% THD
- 150 watts x 2 channels into 4 ohms (20-20,000 Hz) at 0.005% THD
- Direct Digital design yields 90 percent amplifier efficiency
- 4-ohm capability allows use with a wide range of speakers
- signal-to-noise ratio: >95dB (ref. 1W, A-weighted)
- PowerDrive circuit with automatic speaker impedance sensing delivers maximum dynamic power output regardless of speaker load
- Digital Soft Clipping (switchable)
- digital impedance compensation filter allows fine tuning of the top octave to match the speaker impedance (2 to 8-ohm)
- 4 digital audio inputs (2 optical/2 coaxial)
- Modular design construction supports addition of an optional DD-HDM-1 HDMI module for HDMI sources (3 in, 1 out) or a DD AP-1 phono module for connecting a turntable/analog sources
- 2 rear USB inputs (1 type A, 1 type B) support playback of MP3, WMA and FLAC files
- additional USB type A input on front panel
- pre-out/subwoofer out
- two pairs of custom gold-plated speaker binding posts permit bi-wiring
- 12-volt trigger input and output
- 1 IR input
- RS-232 interface for advanced custom installations
- detachable AC power cord
- remote control
- weight: 17 lbs.
- 17-1/8"W x 5-3/16"H x 15-15/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
NAD C 390DD Reviews
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Features and Specs
|Watts RMS per Channel (8-ohms)||150|
|Watts RMS per Channel (6-ohms)||150|
|Watts RMS per Channel (4-ohms)||150|
|Minimum Impedance||2 ohms|
|Signal to Noise Ratio||112|
|Digital Music Features|
|Built-in DAC (Digital to Analog Converter)||Yes|
|High-resolution Audio Playback||FLAC, WAV|
|Total Analog Inputs||0|
|Optical Digital Inputs||2|
|Coaxial Digital Inputs||2|
|Preamp Outputs||Stereo (2)|
|Dimensions and Warranty|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
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 absent.
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 configurations.
- 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 Windows PC, 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 versions.
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 device playability:
- 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 power cord.
Ground Terminal: The NAD C 390DD requires a grounded AC receptacle or a separate earth ground
Our Product Research Team
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