NAD M51 Direct Digital D/A converter Specifications

Sidebar 1: Specifications

Description: Remote-controlled digital-to-analog converter. Digital inputs: AES/EBU (XLR), S/PDIF coaxial & optical, 2 HDMI (stereo only), USB 2.0; all support up to 24-bit/192kHz. Digital output: HDMI. Analog outputs: left & right RCA (unbalanced), left & right XLR (balanced). Output impedance: 47 ohms (unbalanced), 110 ohms (balanced). Output level: 2V RMS. Frequency response: ±0.5dB (ref. 20Hz–96kHz at 192kHz sample rate. Signal/noise: >125dB (ref. 0dBFS 2V out). Channel separation: >115dB (ref. 0dBFS volume –1dB). AC supply: 100–240V, 50–60Hz. Power requirement: 16W.
Dimensions: 17" (435mm) W by 3" (78mm) H by 11.5" (296mm) D. Weight: 12.8 lbs (5.8kg).
Serial number of unit reviewed: H1XM5101162.
Price: $2000. Approximate number of dealers: 250.
Manufacturer: NAD Electronics International, 633 Granite Court, Pickering, Ontario L1W 3K1, Canada. Tel: (800) 263-4641, (905) 831-0799. Web:

NAD Electronics International
633 Granite Court
Pickering, Ontario L1W 3K1
(800) 263-4641

mrhyfy's picture

Great write up seems like a fantastic dac. 

I love the Marantz AV7005 and believe it offers outstanding performance HOWEVER I think you might be doing the Nad a deservice by feeding a $2k dac into a $1700 home theater preamp.

The particular problem for me is that the signal from the Nad has to run through the ADC first,then the dsp then the DAC in the Av7005.Ultimately you're reviewing the dac in the Marantz AV7005!!

 I realize that you used the pure direct mode but it is not analogue pass through in this receiver. 

Would it be possible to evaluate the Nad dac with the signal DIRECTLY connnected  to your amp?  That's the whole point of having the volume control feature in the dac.

Jon Iverson's picture

Whenever I receive a DAC that can also run as a preamp (with volume, input switching, etc), I always connect the DAC directly to my power amps. I then compare this sound to  running via the Marantz in Pure Direct Mode. Rarely have I (or those who are listening with me) ever been able to detect a difference.  To compare to other DACs (which do not have a preamp function) I usually run everything via the Marantz - maybe not perfect, but as fair as I can make it.

VandyMan's picture



I love that they included HDMI, but who only needs two HDMI inputs? I need five and I don't have that complex a system. Before someone suggests adding an external switch, keep in mind that they sometimes causes problems. I have two devices that refuse to work when run thru a switch (and I tried several brands). Besides, one of the points of a "home theater" pre-amp, two channels or not, is to act as a master control switch to all sources.

Surge's picture


Thank you for the review Jon.  I would be really interested in knowing how it compares to the AMR DP-777 that was reviewed in March.

I know the AMR is $5,000 vs. $2,000 for the NAD; but I am curious to know if in your opinion it is worth the additional cost.

Many thanks

Jon Iverson's picture

Surge - I have not yet heard the AMR in my system.

raykkho's picture

Thank you Jon for the very exciting review.  One thing though is how can someone merge his M51 with an existing MC home theatre setup, when the M51 does not have any analogue input or HT bypass? I hate to add an AB switch before the poweramp but can't see how it could be done any other way. sad