[Lappy27]

  i have a question.
in this case - instead of buying an audiophelleo2 and power for about $1000 , would it be comparable just to buy a oppo 105 and use its ability where u connect  a portable hard drive and play music - it can be connected by coax or toslink i believe . then u also gaing with the oppo disc playing abilities sacd/cd/dvda and bluray

The improvment Audiophilleo2 + PurePower brought to my M51 in comparison of his USB input is simply stratospheric.
 
If you have the means even in a stretch, it's definitly money well spent if you're looking for sublime sound reproduction with total absence of noise.
 
Once paid and at the first listen, you will instantly forget about the money and you will congrats yourself every listening session. To all the people who think the M51 sounds good with his USB input, believe me, you only heard about 50% of the M51 potential. This is an absolute serious statement. 

 

[Lappy27]

  i have a question.
in this case - instead of buying an audiophelleo2 and power for about $1000 , would it be comparable just to buy a oppo 105 and use its ability where u connect  a portable hard drive and play music - it can be connected by coax or toslink i believe . then u also gaing with the oppo disc playing abilities sacd/cd/dvda and bluray

The improvment Audiophilleo2 + PurePower brought to my M51 in comparison of his USB input is simply stratospheric.
 
If you have the means even in a stretch, it's definitly money well spent if you're looking for sublime sound reproduction with total absence of noise.
 
Once paid, you will forget about the money and you will congrats yourself every listening session. To all the people who think the M51 sounds good with his USB input, believe me, you only heard about 50% of the M51 potential. This is an absolute serious statement. 

 

[Lappy27]

   
I'm at 1.43 yessir. I'm uncertain why people don't like it. I feel it's better than what I previously had (as said, a very old build, quite possibly the first one that shipped with the DAC seing as I bought it not long after release) but it's a step up for me. Using it paired with a Schiit Mjolnir mainly on my LCD-3's but also my HD-800's. 

I'm still stuck with 1.35 version. I tried to downloaded 1.39 but the display keep saying NO UPDATE FILE. I'm still waiting from NAD tech support about that. If I can't do it myself, I will bring it to a NAD dealer in Montreal. They gonna charge me about 85$ (including taxes) to do it.

 

[screwdriver]

  The improvment Audiophilleo2 + PurePower brought to my M51 in comparison of his USB input is simply stratospheric.
 
If you have the means even in a stretch, it's definitly money well spent if you're looking for sublime sound reproduction with total absence of noise.
 
Once paid, you will forget about the money and you will congrats yourself every listening session. To all the people who think the M51 sounds good with his USB input, believe me, you only heard about 50% of the M51 potential. This is an absolute serious statement. 

i asked because i have been using an oppo 105 to play flac files and this is leaps and bounds better than using computer usb to nad connection , the oppo is connected via coax cable or hdmi cable so no need for usb connection . 

 

[jaycalgary]

I notice a nice improvement with a meaty occc copper power cable.

 

[philo50]

  The improvment Audiophilleo2 + PurePower brought to my M51 in comparison of his USB input is simply stratospheric.
 
 

+1....stratospheric might be a bit much, but the improvement is substantial.....

 

[bdmarion]

I've just spent all of this morning and part of last night trying to figure out a problem with my M51...
 
This was part of the reason I originally asked about putting the iUSB power between my desktop and my M51--I was thinking I was having loop/rf/dirty power issues from my computer.
 
However, the more I looked into trying to fix what I was hearing when outputting USB into my M51, the clearer it became that something was really wrong and this was NOT just something that needed a tweak.
 
The symptom was that whenever I set my audio output on my PC to a high sample rate/bit depth, I would hear this VERY high pitch tone (like a ringing in my ear).  It was dependent on the volume setting of my amp (Woo WA5)--the higher the volume the louder the ringing.
 
I tried switching out literally ALL involved components and cables--including the computer (tried a laptop on battery) and the amp (I have a WA7 here right now, too).  NOTHING made a difference (when the USB was the input to the dac) so I figured I had bad USB output or noise coming directly from the motherboard.
 
I just got the M51 from Crutchfield (open box) for $1599 a few days ago.
 
I called them and they had no idea what the issue was--agreed with me that it might be the motherboard of my pc.
 
As an aside, Crutchfield has WONDERFUL customer service...can't recommend them enough...
 
Anyway, I then called NAD directly and they asked me a lot of questions and had me do a lot of things I'd already tried:
-uninstall and reinstall USB2.0 driver from website
-update firmware to 1.43
-try different components (including plugging in a CD player via digital coax--this was clean, no noise)
-etc.
 
Nothing worked--they were baffled.  Their only thought was that the power supply / motherboard of my pc was doing something "weird."
 
Then I told him I had a NAD C390DD upstairs so I brought it down, plugged it in to the system using all previously used components and cables...GUESS WHAT?  NO NOISE--NICE QUIET SIGNAL!!  This made it clear that the problem is inside the M51.
 
So, it turns out I've got a bad M51.  I called Crutchfield and they, without hesitation, said they'd send me a brand new (not open-box) unit (at the open-box price).
 
I'll be hoping the new one doesn't have any issues (won't be here for a couple weeks--currently out of stock).
 
Has anyone else had anything like this happen with their M51?

 

[ellevoid]

Saw this review on M51, I think "Lab Report" part is pretty interesting.
 
http://nadelectronics.com/img/Marketing/HFN_NAD-M51.pdf

 

[screwdriver]

Bdmarion.how high sample rate?

 

[bdmarion]

Really, it was present at any sample rate if I turned the amp volume up enough.  But, simply put, the higher the bit depth/sample rate, the worse it got.  By the time I was up to 24/192 (not that I really need to be up there), it was distracting at even low volume levels.

 

[screwdriver]

Bdmarion. Few questions. What player are u using to play music files? Did u have other dacs with drivers installed in the computer? What firmware version do u have?

 

[bdmarion]

Bdmarion. Few questions. What player are u using to play music files? Did u have other dacs with drivers installed in the computer? What firmware version do u have?

...yeah, these are among the many things I already dealt with (and was subsequently asked about when I talked to NAD).  The M51 came with 141 and I updated to 143, I removed all other dac drivers from my PC (there was only one), I installed the NAD USB 2.0 driver directly from NAD website and not windows update.
 
For now, at least, I'm using iTunes and pretty much all my tracks are ALAC.  In the future, I plan on changing over to JRiver and will slowly transition into higher res stuff...but for now, iTunes and Apple lossless.
 
Like I said above, I'm quite confident I just ended up with a bad M51.  When I plugged in my C390DD using identical components, cables, drivers, placement, etc...and there were no issues at all, that pretty much made it clear...

 

[screwdriver]

  ...yeah, these are among the many things I already dealt with (and was subsequently asked about when I talked to NAD).  The M51 came with 141 and I updated to 143, I removed all other dac drivers from my PC (there was only one), I installed the NAD USB 2.0 driver directly from NAD website and not windows update.
 
For now, at least, I'm using iTunes and pretty much all my tracks are ALAC.  In the future, I plan on changing over to JRiver and will slowly transition into higher res stuff...but for now, iTunes and Apple lossless.
 
Like I said above, I'm quite confident I just ended up with a bad M51.  When I plugged in my C390DD using identical components, cables, drivers, placement, etc...and there were no issues at all, that pretty much made it clear...

hope u can get it fixed

 

[orkney]

Word to the wise -- I took the plunge to 1.43 from 1.39, and unlike 1.41, I can't revert. Flashing with 1.39 leaves 1.43 installed. No way back, for my unit anyway, it seems.
 
So if you're a 1.39 fan take care in upgrading. You may never be able to go home...again.
 
EDIT: You can get back to 1.39 via 1.41 -- 1.43 >>> 1.41 >>> 1.39. PITA, but it works, and confirms 1.39 as the best-sounding to date, to my ears at least.
 
best,
 
o 

 

[olor1n]

Thanks for the heads up.

1.39 for life!