The NAD C 658 is a new kind of stereo component, one that at once changes preconceptions and opens new possibilities for audio reproduction. You see, there has never before been a component offering such a rich palette of both new and proven technology. Bold statements? Read on. 

NAD BluOS Streaming DAC C658:
Type: Streaming DAC with Preamp and Phono Stage

Line Input, Pre-Out Performance:
THD (20Hz – 20kHz): <0.005% at 2V out
Signal-to-Noise Ratio: >106dB (IHF; A-weighted, ref. 500mV out, unity gain)
Channel Separation: >80dB (1kHz), >70dB (10kHz)
Input Impedance: 22 kΩ + 100pF
Maximum Input Signal: >4.5Vrms (ref. 0.1% THD)
Output Impedance: Source Z + 240 Ω
Input Sensitivity: 93mV (ref. 500mV out, Volume maximum)
Frequency Response: ±0.3dB (20Hz – 20kHz)
Maximum Voltage Output: >4.5V (ref. 0.1% THD)
Tone Controls: Treble: ±7.0dB at 20kHz; Bass: ±7.0dB at 60Hz; Balance: -10dB

Phono Input, Audio Pre-Out Performance:
THD (20Hz – 20kHz): <0.01% at 2V out
Signal-to-Noise Ratio: >84dB (200Ω source; A-weighted), >76dB (MM cartridge source, IHF A-weighted, ref. 500mV out)
Input Sensitivity: 1.44mV (ref. 500mV out, Volume maximum)
Frequency Response: >±0.3dB (20Hz – 20kHz)
Maximum Input Signal at 1kHz: >80mVrms (ref. 0.1% THD)

Line Input, Headphone Out Performance:
THD (20Hz – 20kHz): <0.005% at 1V out
Signal-to-Noise Ratio: >110dB (32Ω loads; A-WTD, ref. 2V out, unity gain)
Frequency Response: ±0.3dB (20Hz – 20kHz)
Channel Separation: >>60dB at 1kHz
Output Impedance: 6 Ω

DAC Section:
Supported Audio File Formats: MP3, AAC, WMA, OGG, WMA-L, ALAC, OPUS
High Resolution Audio Formats: MQA, FLAC, WAV, AIFF
DSD Playback: Supports converted DSD playback via BluOS desktop app (only)
Native Sampling Rates: up to 32bit/192kHz
Bit Depths: 16 – 24

BluOS Features:
Supported Operating Systems: Microsoft Windows XP to current, Mac OS X versions
User Interface: BluOS – Free Android and iOS App
Supported Cloud Services: Spotify, Amazon Music, TIDAL, Deezer, Qobuz, HDTracks, HighResAudio, Murfie, JUKE, Napster, Slacker Radio, KKBox, Bugs
Free Internet Radio: TuneIn Radio, iHeartRadio, Calm Radio, Radio Paradise

Connectivity:
Bluetooth: Bluetooth aptX HD wireless built-in, Two-Way (Transmit and Receive)
Network: Gigabit Ethernet RJ45, WiFi 5 (802.11 b/g/n)
Analog Inputs: Line Input, Phono Input (MM)
Headphone Output: 6.35mm (1/4") jack
Digital Outputs: Pre-Out (RCA)
Other Outputs: Subwoofer Output (RCA)

General:
Dimensions (W x H x D): 435 x 100 x 405mm (17 1/8 x 3 15/16 x 16")
Shipping Weight: 10.1kg (22.3lb)