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NAD M66 - finally someone makes a decent 2-channel preamp!

If you have a setup with subwoofers and the subwoofers do strange things when "analog direct" is engaged, then there is no "analog direct"
Of course, you have analog direct for the left and right channels. Perhaps the block diagram makes it easier to understand:

Screenshot_20250415-235427_Chrome.jpg


I have highlighted the parallel tap of the analog signals in yellow up to the sub-outs. In analog direct mode, the sub-out signals should be suppressed (firmware update needed).
Currently, you can simply switch off the subs if you want to listen to pure analog.
 
Not to mention the out of sync subs that should not be playing at all.
Yes, this is what I don't get. Obviously, something other than just the STEREO L/R is being integrated in with the ANALOG-only pathway (I get it; they have only one volume control-out pathway, and it seems they didn't design it for a separate ANALOG-only in/out pathway). Otherwise, you could not have the subs being involved with the ANALOG-only pathway. But, apparently, when you choose ANALOG-only, and have connected subs, you get out-of-synch subs. The NAD Audio Path diagram shows subwoofers only being included as a part of Blu-OS/Dirac processing (which should NOT be a part of an ANALOG-only pathway), but it seems to me NAD's very elementary graphic depiction of the audio pathway may not be what they really thought it should be as an ANALOG-only path. And that's why I cannot trust that they will ever get it right except for a new hardware release of a M66 V.2 (isn't that what they always do -- let the consumers be the beta-testers)? I may be wrong with this thinking, so please correct me if I am. The M66 used to be my next hopeful and final preamp -- for a short season. With all of its uncorrected faults and/or design deficiencies, I could never go for it as is. On the other hand, I think that NAD amps, for the most part, ROCK!
 
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they have only one volume control-out pathway, and it seems they didn't design it for a separate ANALOG-only in/out pathway
That is not correct. The volume controls L/R shown in the upper half of the block diagram are only implemented for the purely analog stereo signal. The branch I highlighted in yellow shows the parallel tap before the analog volume control. The parallel tap path works like the preamplifier section of an M33, i.e. volume control is carried out in the digital domain. The block diagram only shows the flow of the audio signal and not the control signals, etc. It also does not require a V2 to mute the subouts ;)
 
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(firmware update needed).
I am searching for an appropriate smiley:
:facepalm: or :eek:or:(or:mad: or was this one meant: ;)

To be serious: Has NAD warned in the manual that there is wrong or no output with analog direct engaged?
I already wrote it a few months ago that this is not only important for a "Home Cinema Bypass". If you want to listen to your vinyls or use the analog output of a SACD-Player you have to choose between wrong bass or no bass. Correct?
Nocko!
 
If you want to listen to your vinyls or use the analog output of a SACD-Player you have to choose between wrong bass or no bass. Correct?
In these cases, I would not choose the pure analog path, but use DLBC or, in the future, DLART. A better integration of subs is difficult to find.
If you really only want to use the pure analog path, the subs have to be connected to the normal preamplifier outputs (not sub outs) with the known problems of not quite simple integration with regard to latency, phase, ...
 
M66 (sorry, couldn't resist either...)
:)
In these cases, I would not choose the pure analog path, but use DLBC...
Soundwise I am with you. But I have learned here, that there are people around who don't like or don't need Dirac. Also I can understand that vinyl afficionados or folks who still like tapes don't want their precious signal digitized. And why is NAD advertising "direct analog" without explaining that this renders the four (!) subwoofer outputs absolutely useless. The more I think about it, the worse it gets...
Nocko!
 
And why is NAD advertising "direct analog" without explaining that this renders the four (!) subwoofer outputs absolutely useless.
They do not have to explain this, as it cannot be intentional on the part of NAD. An FW update will probably prevent this in the future.

Here's a story about my M33.
Until recently, the Dirac Live filters were also applied via the headphone output if they were not deactivated beforehand. After more than four years, this 'bug' has now been corrected. There must have been many user requests for this.
For me personally, it's a bit of a disaster, as this 'bug' also allowed me to equalize my headphones via a special DL project ;)
 
They do not have to explain this, as it cannot be intentional on the part of NAD. An FW update will probably prevent this in the future.

Here's a story about my M33.
Until recently, the Dirac Live filters were also applied via the headphone output if they were not deactivated beforehand. After more than four years, this 'bug' has now been corrected. There must have been many user requests for this.
For me personally, it's a bit of a disaster, as this 'bug' also allowed me to equalize my headphones via a special DL project ;)
On the contrary. Any manufacturer, when printing the device datasheet and user manual, and putting out features, are responsible for the features to work exactly as stated in the marketing material and user instructions manual. A consumer can hold the manufacturer responsible for false advertising and fraud if the device does not comply to the advertised and described functions. The device can be deemed defective even if one of the advertised functions does not work.
At the time (July 2024) when I purchased NAD M66, quite a few functions listed in the user manual and data sheet did not work. It was my decision to wait a litle and see how things go. NAD implemented a couple of features that were in the data sheet, but there are more remaining with a future unspecified date. My patience has ended, and unfinished product should not be pushed to market. I can understand if there was a notice up-front, that a certain feature (like ART) will be in the future. But listed features should work, else the device is defective as manufactured.
If, indeed, the analog direct behavior is not intentional, than it means only one thing - NAD did not test it. As such, we come back to false advertising and marketing fraud. And they should strive to fix it ASAP.
I am mostly irritated by their standard response for my tickets - "we will pass it to our QA and Dev labs for future consideration in BluOS release" without any commitment and date. And I am talking about features that are listed in the data sheet and user manual.
 
If, indeed, the analog direct behavior is not intentional, than it means only one thing - NAD did not test it. As such, we come back to false advertising and marketing fraud. And they should strive to fix it ASAP.
It should be clear what is meant by Analog Direct/Analog Pure. This means that there is no influence on the sound. There is also no active sub management.
Only the volume setting and the analog source can be selected.
 
After more than four years, this 'bug' has now been corrected...
:eek:
You must be unbelievably patient. The only thing that rectifies this loyalty is that there are nearly no stereo amps with Dirac built in. And I believe that the M33 is completely different from the M66. If it is constructed like the older amps from the Master-Series (an amp with a built in streamer and not the other way round...) this might explain why you always defend the M66.
Nocko!
 
I am not defending the M66.
I'm just trying to explain how the M66 works, as the complexity is probably too much for some people.
Something similar is happening at Dirac, who are working on a new user interface, especially for DLART.
 
I am also still following this thread while already decided to never buy NAD again. I guess something is wrong with us Nocko!!
 
We've been through this before....
My M33 still has coil noise, a useless remote, and frequently HDMI CEC fails. Not to mention BluOS that is a disaster since V4. I only follow this thread to remind me to never buy NAD again.
 
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