NAD C399 Integrated Amplifier

NAD C399 Integrated Amplifier Review

The NAD C399 integrated amplifier is a high-end integrated amplifier designed for audiophiles who demand exceptional sound quality and versatility. It is part of NAD’s Classic Series, which aims to provide uncompromising performance and affordability. The NAD C399 integrated amplifier is a powerful and sophisticated amplifier, making it capable of driving even the most demanding speakers. It is also equipped with NAD’s proprietary PowerDrive technology, ensuring the amplifier can deliver maximum power with minimal distortion.

In addition to its impressive power and technical features, the C399 integrated amplifier is highly flexible, with a range of inputs and outputs that make it suitable for various audio sources and setups. Overall, the NAD C399 is a top-performing amplifier that offers exceptional sound quality and versatility at an affordable price. This review will examine its features, performance, and overall value for money.

NAD C399 Integrated Amplifier


The NAD C399 leaves a strong first impression with its solid and reliable chassis structure. Even before it’s turned on to make a sound, the cover plates feel thick and reassuring. While it may not be as tough as a tank, its design instills confidence in its durability. The exterior design of the C399 is intentionally simple, lacking the layered and color-separated decoration of the M33 and other Master series models. The relatively small and monochromatic display screen further emphasizes this simplicity.

The only decoration is the trimmed arcs imitating the M33 at the left and right corners of the front panel. However, NAD has always prioritized sound quality over aesthetics. Similar to the iconic 3020 model from the past, the C399 remains refreshingly simple and unpretentious.

NAD C399 Integrated Amplifier

The NAD C399 integrated amplifier is a feature-rich device demonstrating the brand’s commitment to delivering a high-performance audio experience. Its back terminals include two high-level analog inputs (RCA) sets, an MM phono amplifier input (RCA), and two coaxial and optical fiber digital inputs. Notably, NAD has designed the C399’s phono amplifier circuit with a precise RIAA EQ curve, resulting in a high signal-to-noise ratio and an infrasonic filtering function that effectively eliminates extremely low-frequency noise.

The C399 also boasts two rare and convenient features for comprehensive expansion: Bluetooth transmission and HDMI. The latter supports eARC for audio and video synchronization when connected to a TV for movie watching. Overall, the C399 is a versatile and reliable device that enhances audio setup.

NAD C399 Integrated Amplifier

The NAD C399’s Bluetooth transmission capabilities are a standout feature of this device. It supports aptX HD 24-bit audio, a significant upgrade over the 16-bit aptX level found in previous C388 and C368 models. The C399’s Bluetooth functionality also supports two-way transmission, allowing it to receive and send signals.

That makes it possible for users to connect the device to a Bluetooth headset and stream audio from the C399 directly to the headset. This feature is not available on earlier NAD models, making the C399 an excellent choice for users seeking the convenience and versatility of Bluetooth connectivity.

NAD C399 Integrated Amplifier

The NAD C399 integrated amplifier is more than just an integrated amplifier; it also features a built-in DAC that allows users to connect a wide range of digital source equipment, such as TV boxes, game consoles, CD players, and Blu-ray players. While the standard configuration of the C399 includes only four sets of S/PDIF inputs (two coaxial and two optical) and Bluetooth and HDMI inputs, this is generally sufficient for most household needs.

However, it’s worth noting that the USB type-A port on the back of the C399 is not intended for use with hard disks or flash drives. Instead, it should only be used for maintenance or firmware upgrades. Be sure to exercise caution when inserting devices into this port.

NAD C399 Integrated Amplifier

One of the standout features of the NAD C399 integrated amplifier is its use of the ESS Sabre 9028 DAC chip, which is also found in the high-end Master series. This chip can support up to 32bit/384kHz, although the C399’s S/PDIF digital inputs can only accommodate up to 24bit/192kHz. Nevertheless, this still substantially improves over the standard Red Book specification of 16bit/44.1kHz, resulting in a more immersive and satisfying listening experience, especially for high-resolution music.

The menu of the NAD C399 integrated amplifier is exceptionally rich in functions, allowing users to personalize settings according to their preferences. The circular coaxial control buttons on the front panel’s left side are easy to operate. Users can press the buttons in four directions, up, down, left, and right, and the central button is for selecting the input. In addition to the standard high and low volume adjustment and left and right channel balance, the C399 also allows users to control the on and off of each group of inputs and name each group of inputs.

NAD C399 Integrated Amplifier

It also offers the option to choose between variable volume or fixed volume control, with the latter being valid for surround preamps. If the output of the front-end source is low when using the analog input, users can increase the gain of the analog input in the menu.

The NAD C399 integrated amplifier is a versatile and high-performing integrated amplifier that offers excellent sound quality and connectivity options and a range of customizable settings for a personalized listening experience. With features like the HDMI bidirectional channel and Auto Sense function, users can easily control the C399 through a linked TV and wake it up with a signal from the source device.

NAD C399 Integrated Amplifier

The display screen brightness and volume display method can also be adjusted, among other customizable settings. The C399’s menu operation is user-friendly and intuitive, making it easy for users to fine-tune their listening experience. Overall, the NAD C399 is a top-of-the-line integrated amplifier with many features and options for audio enthusiasts.

The C399’s output options provide versatility and flexibility for different speaker setups and audio systems. With two speaker terminals, you can easily connect two or bi-wire your speakers using two pairs of speaker wires. Additionally, the pre-amplifier outputs allow you to connect to other post-amplifiers, while the speaker output can be used for bi-amp dual amplifiers.

NAD C399 Integrated Amplifier

Compared to its predecessor, the C388, which only had one set of pre-outputs, the C399 integrated amplifier has two subwoofer outputs, allowing you to play a subwoofer in addition to bi-amping or using a subwoofer with a single amp. This feature can significantly enhance the bass performance of your audio system.

The C399 also includes a 6.3mm single-ended headphone output jack on the left side of the front panel, which provides users with a convenient way to listen to music using wired headphones. The headphone output of the C399 is of high quality, providing a clear and powerful sound. For instance, when using Sennheiser HD598 headphones to listen to “Black Eyes” from the movie “A Star is Born” through Tidal Connect, the C399 produced a rich and dynamic sound, making the HD598 headphones sound more vibrant and engaging. The powerful drums and Bradley Cooper’s slightly raspy voice were delivered with a clear and solid presence through the C399’s headphone output.

NAD C399 Integrated Amplifier

NAD C399 is a high-quality amplifier and a versatile audio-visual control center. Its RS232 serial port, 12V Trigger power trigger linkage, and IR infrared input and output linkage terminals allow users to efficiently plan and integrate it into their home smart control system. NAD also supports intelligent control system manufacturers, such as Control4, Crestron, RTI, URC, Lutorn, IPort, Elan, PUSH, and KNX, making it a flexible and convenient option for smart home enthusiasts.

NAD C399 is not just another run-of-the-mill audio equipment you buy and leave at that. It stands out because of its modular design structure, first introduced in 2006 as MDC (Modular Design Construction). With MDC, you can purchase modules that expand the functions of your NAD C399 integrated amplifier, allowing you to customize your system according to your needs. And now, with the new generation of MDC2 modules, the possibilities are even more significant.

NAD C399 Integrated Amplifier

The first MDC2 module, MDC2 BluOS-D, has two exceptional functions. One is the Dirac Live space correction, which helps to optimize your listening experience, and the other is BluOS music streaming, which allows you to stream your favorite music wirelessly. It’s worth noting that the C399 is the first NAD device that can be installed with the MDC2 BluOS-D second-generation MDC modules, making it even more versatile and future-proof.

Spatial correction is a type of digital signal processing (DSP) used to correct distortions caused by the room’s acoustics. While some people may prefer something other than the sound after spatial correction, it can be a convenient solution for users facing poor room acoustics. The Dirac Live technology integrated into the MDC2 BluOS-D module primarily addresses peaks and dips at 500Hz, a problematic frequency range in most rooms. It can also optimize frequency response peaks caused by reflection sounds from room walls.

NAD C399 Integrated Amplifier

The included microphone and Dirac Live software improves the bass clarity and overall audio image, resulting in a more accurate timbre. The software can remember up to five listening positions, making it easy to get room-corrected sound no matter where you sit. The MDC2 BluOS-D is the first NAD device to incorporate Dirac Live space correction technology into an MDC module for use with two-channel equipment.

The music streaming function of the MDC2 BluOS-D module is an excellent addition to the NAD C399. With wired and wireless connectivity options, users can easily connect the amplifier to the Internet and stream music from various sources.

NAD C399 Integrated Amplifier

The support for popular streaming services such as Spotify Connect and Tidal Connect means that users can use their respective apps to stream music to the amplifier directly. Additionally, support for UPnP/DLNA playback and Roon Ready certification provides users with even more options to stream high-quality music.

Moreover, the support for high-resolution audio up to 24bit/192kHz and MQA decoding means that users can enjoy high-quality music without compromising sound quality. Apple users can take advantage of the AirPlay 2 and Siri voice assistant integration. Amazon Alexa and Google Assistant support make the NAD C399 a versatile device that can integrate into various intelligent home setups.

Overall, the music streaming functionality of the MDC2 BluOS-D module adds excellent value to the NAD C399 and makes it an even more compelling choice for audiophiles who want to stream music from a variety of sources.

NAD C399 Integrated Amplifier

The MDC2 BluOS-D module’s Bluetooth functionality is also a two-way Bluetooth, which may raise concerns about potential conflicts with the built-in Bluetooth of the C399 once the module is installed. However, NAD’s engineers have already considered this. After installing the module, the C399’s built-in Bluetooth will be turned off, and the Bluetooth of the MDC2 BluOS-D will be used instead. That ensures that only one pairing target will appear on your mobile phone, eliminating confusion.

This problem was not noticed in the era of the C388, but NAD has now solved this issue with the MDC2 BluOS-D. Furthermore, the original C399 does not have a USB jack for connecting hard disks with music files. Fortunately, the MDC2 BluOS-D includes a USB type A jack, increasing the overall flexibility of use.

With the addition of the MDC2 BluOS-D module, the NAD C399 integrated amplifier, which initially lacked streaming capabilities, is transformed into a versatile streaming integrated amplifier that can address sound distortion caused by home acoustics. This single module provides all these functions, making the Classic series C399 the first entry-level integrated amplifier to compete with the Master series models.

NAD C399 Integrated Amplifier

Yes, NAD’s MDC module design allows for future upgradability and customization of their amplifiers. As technology advances and new features become available, NAD can develop and release new MDC modules that can be easily installed into their existing amplifiers, providing users with the latest features and capabilities without buying a new one. This design philosophy not only benefits users by making their investment in a NAD amplifier more future-proof, but it also reduces waste and helps the environment by extending the product’s usable life.

NAD’s DirectDigital technology is a fully digital amplification technology that converts the audio signal to a high-resolution digital signal before amplification, eliminating many of the distortions and noise associated with analog amplifiers. This technology allows for a much more accurate and transparent audio signal amplification with a high degree of linearity and low distortion.

On the other hand, Class D amplification, also known as switching amplification, is a type of analog amplification that uses a pulse-width modulation (PWM) technique to switch the audio signal on and off at high frequencies. That allows for high power efficiency, low heat dissipation, and a small-size amplifier.

NAD’s adoption of Class D amplification allowed them to create high-power, high-performance amplifiers in a small form factor while maintaining their signature sound quality and affordability. Both audiophiles and the general public have well received this move towards digital and Class D amplification, as NAD continues to produce award-winning amplifiers that are both powerful and affordable.

NAD C399 Integrated Amplifier

NAD’s current amplifiers use a variety of amplifier modules, including Purifi Audio’s Eigentakt and Hypex modules. The C388 uses the Hypex UcD amplifier module, while the NAD C399 integrated amplifier uses the same Hypex nCore module as the higher-end M10 amplifier. The M10 uses a single set of stereo nCore modules with a maximum output of 100W, while the C399 uses two sets of nCore modules of the same type, resulting in an output power of 180W per channel and a peak output of 250W, which is higher than the C388’s 150W.

The customized Hypex nCore amplifier module used in the C399, tuned by NAD, boasts wide bandwidth and a flat frequency response, according to the manufacturer. The module also features ultra-low noise and distortion, maintaining low distortion even at high volume output. Additionally, the current high production enables the C399 to handle speakers with low impedance without fear.

The C399 can be seen as an affordable version of the M33 for several reasons. First, it uses the same Hypex nCore amplifier module as the M10, and with two sets of these modules, it has a more productive power output. Additionally, regarding digital functions, the C399 is on par with the M10 and M33 of the Master series. Despite having a more straightforward appearance than the M33, the C399 is close to it in terms of function and performance.

NAD C399 Integrated Amplifier

Even regarding the back panel, the C399 is almost the same as the M33, except lacking XLR analog balanced input and AES/EBU digital input. The C399 can be considered a “pseudo-Classic” model and a master-level device in the Classic series. It offers comparable features and performance to the M33 at a more affordable price. The C399’s full-size body also allows for better heat dissipation, preventing the machine from becoming too hot during intense use.

Indeed, the MDC module planning design is an excellent advantage of the C399, allowing it to keep up with future technology and user needs. By adding new modules, users can upgrade their C399 without replacing the entire amplifier. This also adds value to the product as it can evolve. With the latest MDC2 BluOS-D module, the C399 gains streaming capabilities and Dirac Live room correction, making it a versatile and powerful device. The C399 may look simple, but it can significantly impact the market.

Sound Performance

The sound performance of the C399 is indeed impressive. Its Hypex nCore amplifier module delivers clean and detailed sound, with high resolution and density, that allows even the most minor details in the music to be revealed. The sound signature of the C399 is lively and bright, with a youthful and energetic temperament. The soundstage is wide and well-structured, allowing large-scale music to be played with clarity and precision.

Unlike traditional Class D amplification, the NAD C399 integrated amplifier does not have problems with excessive bass. Instead, it produces strong, fast, and clean bass with moderate volume and excellent resolution in the low range. Overall, the sound of the C399 is clean, detailed, and well-balanced, making it a perfect choice for music enthusiasts who value high-quality sound performance.

NAD C399 Integrated Amplifier

The C399 can deliver a dynamic and exciting listening experience with excellent resolution and detail. The Hypex nCore amplifier module provides a clean and detailed sound, with strong and fast bass, that maintains its resolution even at high volumes. It’s interesting to hear how the C399 performs with different types of music, such as the soundtrack to “Top Gun: Maverick,” where it’s able to bring out the tension and drama of the music while still maintaining clarity and texture. And it’s great to hear that the C399 can also handle electric guitar playing with a wild and aggressive tone, making for an enjoyable listening experience.

The C399’s ability to faithfully reproduce orchestral music’s intricate textures and intricate details is remarkable. Its high resolution and expansive soundstage deliver a crystal-clear and transparent listening experience, enabling the listener to discern and appreciate the music’s components and the overall orchestral performance.

The dynamic range of the C399 integrated amplifier is also impressive, capturing the most delicate nuances of a solo instrument while also delivering the thunderous crescendos of a full orchestra. NAD’s decision to prioritize clarity and transparency over warmth and softness has undoubtedly paid off, resulting in a powerful and energetic sound that genuinely showcases the music’s finest qualities.

I am glad you appreciate the NAD C399’s ability to drive speakers with its powerful and dynamic performance. The C399’s ability to provide a clean, transparent, and clear sound texture allows you to fully appreciate the organization of the music and the speaker’s capabilities.

Even when playing music at low and medium volumes, the detailed sound quality of the C399 is comparable to that of a small power amplifier. The C399’s high-power output allows it to easily drive even the most demanding speakers, including the Dynaudio Contour 60 and Wilson Audio Alexia 2, which are much more expensive than the C399. The majesty and dynamic margin of the C399, when pushed to high power, are hard to match with a small-wattage amplifier, making it an exceptional choice for those who value both refined sound and powerful performance.


In conclusion, the NAD C399 integrated amplifier is a remarkably integrated amplifier that represents the pinnacle of NAD’s 50 years of experience and innovation. Its ability to reproduce music with exceptional clarity, transparency, and dynamic range is truly impressive, and its powerful driving force can bring out the best in any speaker. The C399’s sleek and minimalist design makes it a stylish addition to any home audio system.

With features such as high-resolution digital inputs, wireless streaming capabilities, and modular design, the C399 is a versatile and future-proof amplifier that can adapt to the ever-evolving needs of audiophiles. Its exceptional sound quality and versatility make it a worthwhile investment for anyone who values a premium listening experience.

Overall, the NAD C399 integrated amplifier is a testament to NAD’s commitment to excellence and innovation. Its 50 years of experience have culminated in an amplifier that sets the standard for high-performance integrated amplifiers. If you’re in the market for a high-end integrated amplifier that delivers an unparalleled listening experience, the NAD C399 is worth considering.

Specifications of the NAD C399 Integrated Amplifier

  • Continuous Output Power (Stereo): > 180 W
  • Total Harmonic Distortion (20Hz-20kHz): <0.02% (250mW to 180 W, 8Ω and 4Ω)
  • Signal-to-noise ratio: >95dB
  • Damping factor: >150 (ref. 8 Ω, 20Hz and 6.5kHtz)
  • Frequency response: 20Hz-20kHz
  • Standby power: <0.5W
  • Digital input terminal: coaxial x 2, optical x2
  • Analog input terminal: Line In x2, MM phono amplifier (input sensitivity: 0.3mV, ref. 200mV pre-out)
  • Dimensions (W x H x D): 435 x 120 x 390 mm (17 1/8 x 4 3/4 x 15 3/8)”