Setting the sampling rate this high was a solution to move the effect of the filters out of the audio band, and sometimes quite audibly so. You would still have a filter, but its effect in audible sounds was next to nothing since it would begin its work at the 40Hkz range. One of the many times...

Certainly, and even a better example is loud concert. The conversation you have afterwards is oddly loud for good reason. I'm also quite sure that if you measured the sustained dynamic range of hearing across various frequencies, it would also show some significant curves with wide variations...

While you will only be able to discern sound up to 40db below the RMS power of a track, you can withstand significantly more above that in a short impulse. Again, no one would use it as it has limited practical purpose. Another thing to note is that our hearing has significantly different...

Human impulse dynamic hearing can reach 120db. Granted you wouldn't want to do it all day, unless you really would like to eventually shut out the rest of the world.

For the vast majority of consumers, its generally correct for a variety of reasons. In comparing 16 bit to 24 bit recording depth, people can hear dynamics beyond a the 16 bit level, only a limited number of playback devices are capable of resolving that data in analog performance. The iPhone 6...

The rear outputs are fixed and the volume knob in the from controls the headphone amplifier.

The M51 does run a bit above specifications when it comes to output voltage. If the input stages on your preamp do not handle above 2V for single ended or 4V for balanced, it will likely result in  distortion. My M51 has no distortion at any point and I was able to test both outputs in my setup...

After going through tests between the Wadia 121 DAC and NAD M51 both direct and though preamp, I can quite easily affirm the digital volume control provided by the M51 as the better of two. The gap between the two products actually widened when going direct as the NAD seems to do no harm to high...

I just started using the M51 without my preamp and it seems to drive everything quite well. I will try a session between the two over the weekend and provide some notes on what I hear.

I will also give a thumbs up to the NAD M51. I actually have a Wadia 121 DAC in house for comparison and the M51 is ahead in most areas. I just began my direct DAC to amp to see how I like it without any preamp in the way.   Another Head-Fi user had compared the M51 to the Audio GD and...

I picked up my own for $1760 USD, including shipping.

I certainly understand and this also is something that is a matter of perspective and preference. I agree with the sentiments that is within a certain price range, but in the case with this NAD, it seems to a significant degree upward. My Marantz SA-11S1 was always regarded as a very good red...

I would be astonished if the M51 didn't achieve exemplary measurements. I'm using the NAD M2 as a reference for measurements and it was given a clean bill of health. The proof is in the pudding, so to speak, and NAD is most certainly delivering.   I will state that all my listening has been...

Well after the first day of break in for the Wadia 121 DAC, it now faced its first session against the NAD M51. I can't heap enough praise on the NAD M51 as it showed a clear and significant step up from the Wadia. Its truly sounding wonderful in my system and I have not even tried it direct to...

I have the Wadia 121 DAC breaking in at home now and will let you know what I think of it in the near future. I will say that first initial hearing is mixed as I heard a a wide, but not very deep sound stage. Dynamics were also some what on the short side.