The NAD C658 is a stereo preamplifier with digital-to-analog converter and network streamer. The model is based on the BluOS streaming platform, which was developed for the Bluesound family of devices, and then adapted for other Lenbrook-owned brands, including NAD Electronics, and subsequently licensed to third parties such as DALI. The BluOS platform and the accompanying mobile app provide access to a wide range of music and radio services, including Spotify, Amazon Music, Tidal, Deezer, Qobuz, HDTracks, Napster, TuneIn Radio and iHeartRadio. It also supports playback of audio files, both local and on network servers, with parameters up to 32-bit/192 kHz and the MQA container – the indexed library contains more than 250,000 tracks.
The platform allows you to connect with other BluOS players, and thanks to a recent update, it now offers an additional connectivity option — AirPlay 2 for multi-room streaming and streaming from Apple devices. The BluOS app is available for iOS, Android, Windows, and Mac OS, setting a new standard among streaming platforms. The BluOS app is easy to navigate, with a side drop-down menu listing sources and services, as well as links for quick access to favorites and playlists. It’s a well-designed and reliable app; even switching between music services or navigating to a local library is smooth and lag-free.
The NAD C 658 preamplifier is a two-way wireless Bluetooth interface with aptX HD, which provides high-resolution audio transmission to compatible wireless headphones, and also allows you to receive music via Bluetooth from a smartphone or other mobile gadget. In addition, the NAD C 658 can serve as the core of a multi-component audio system, as it is equipped with digital inputs, including two optical, two coaxial and one USB (all signals go to the 32-bit ESS Sabre DAC), as well as analog – two line inputs on RCA connectors and an MM phono preamplifier input for connecting a vinyl player.
Recognizing that standards and technologies in the audio industry are constantly evolving, NAD Electronics has given the C 658 a modular design – a signature feature of the brand. For expanded functionality, two dedicated slots are provided, one of which can accept the already available NAD HDMI module with 4K passthrough support, making it easy to connect game consoles, Blu-ray players or TV boxes.
The NAD C 658 preamplifier features Dirac Live , an automatic room calibration system that is also used in the top-of-the-line NAD M10 and some NAD multichannel components. This technology measures the acoustics of a room and optimizes the unit’s performance. This is a rare feature in stereo components.
Technical specifications of the NAD C 658 network preamplifier:
- DAC: ESS Sabre with MQA support
- OS: BluOS
- Room Calibration: Dirac Live
- Supported formats: MQA, WAV, FLAC, AIFF (AIF, AIFC), MP3, AAC (M4A, MP4), WMA, OGG, ALAC (M4A), WMA-L
- Streaming Services : CALM Radio, iHeartRadio, Radio Paradise, Slacker Radio, TuneIn, Deezer, Groove, JUKE, Murfie, Napster, Qobuz, Spotify, Tidal, WiMP
- Network and wireless : Gigabit Ethernet (RJ-45), Wi-Fi (a/c/n, dual-band), two-way Bluetooth aptX HD
- Audio inputs: Phono, 2 RCA line inputs, 2 optical digital inputs, 2 coaxial digital inputs, USB
- Audio outputs: balanced adjustable (XLR), unbalanced adjustable (RCA), active subwoofer output
- Expansion slots: 2 MDC slots
- Headphone amplifier: built-in
- Dimensions (W x H x D): 435 x 100 x 405 mm
- Weight: 10.1 kg
