NAD C 658 Review: The core of your home audio system
The NAD C 658 is a BluOS DAC, preamp, and streamer in a single device that boasts one of the most advanced BluOS high definition streaming systems available.
Essentially, the preamp is becoming a node in the BluOS ecosystem, delivering 64-zone high-definition network streaming and control capabilities for iOS, Android, Windows and Mac OS phones, tablets and desktops. BluOS also supports all major smart home controllers and is available in a wide range of products, making it easy and affordable to build a whole home audio system with the C658 at its core. Responsible for signal processing is a DAC with chips from ESS, capable of decoding MQA.
The NAD C 658 lets you stream high definition music from nearly 20 music streaming services, offers full MQA decoding on all digital inputs, and supports aptX HD Bluetooth two-way communication. The audiophile-caliber Direct Digital DAC delivers superior fidelity with a staggering 130dB dynamic range, while the built-in MM phono preamp, dedicated high current headphone amplifier and Dirac Live Room Correction software make the fully modular NAD C 658 a treasure alike. capable of serving digital and analogue needs. In addition, a balanced pre-out, stereo sub-out and RS-232 serial port add flexibility.
The NAD C 658 comes with a microphone, so users can measure and calibrate their listening environment using the Dirac app, which stores up to five different listening profiles and is available for desktop, iOS and Android devices. Room correction and tone controls are available through the Dirac app, while NAD’s Bluad Controller app provides controls for selecting filters, adjusting the subwoofer crossover, and disabling Dirac processing.
NAD C 658 includes a “lightweight” version of Dirac Live, which only provides compensation up to 500 Hz. To achieve room correction across the entire frequency range, NAD C 658 owners will have to upgrade to Dirac Live Full at an additional cost.
Dirac Live processing compensates for room acoustic imperfections by first measuring the power and time required for direct and reflected sound waves to travel from the speakers to a user-defined listening area, then applying equalization filters to achieve natural sound without altering the audio system’s own sound characteristics.
The NAD C 658 includes a unique Modular Design Construction feature that is exclusive to NAD. With MDC, all major digital circuits can be upgraded and replaced to keep the device up-to-date forever. This NAD innovation is a unique architecture that keeps pace with the rapidly changing world of technology.
With MDC, the ability to easily update a component to include future digital formats is completely unique and unprecedented. While installation and configuration of any MDC module is straightforward, consumers are advised to ensure that this update is professionally installed by their authorized dealer. The NAD C 658 DAC comes with two MDC slots for future expansion.
NAD engineers have not forgotten traditional audiophiles by incorporating high-quality switching: analog inputs, balanced pre-out and stereo subwoofer outputs, and a dedicated high-frequency headphone amplifier with a 1/4 “jack on the front panel. CI enthusiasts will be pleased to know that the NAD C 658 has serial RS-232 port with certificates and chassis drivers ready for Control4, Crestron, RTI, URC and ELAN.