Anybody else get a NAD M66 yet?

I took delivery of a new NAD M66 preamp last week.  I’m curious if anyone else has one yet?  One reason I was interested in it was the all-analogue pathway having a resister ladder relay volume control.  The early videos posted by NAD demonstrated the volume control clicking (as resistor ladders will do…).  Mine does not, even when in analogue bypass mode using an external source.  I’m wondering if they changed the design or if mine is not working properly.  

Initial impressions are mixed, but it’s too early to make determinations.  The other reason I wanted to try it out is for the DIRAC live and bass control capability.  After playing around with the DIRAC, I can say it definitely makes a big difference in my asymmetrical room.  I finally get non-boomy bass and hear all the low notes consistently.  It does seem to take a bit out of the transparency of the overall sound, but again, too early to make final judgments.

Overall, it works well and sounds pretty good, but they still have some bugs to work out, which were expected I think, given the delayed release. For example, if you are using a source with the all digital processing (like the internal DAC), and have subwoofers connected as I do, then switch to an external source with analogue bypass, the subwoofers still seem to be stuck in digital processIng and lag behind the main speakers.  Also, playing around with the various settings in analogue bypass and in the digital domain have left me with an error message, and the unit reboots itself.

Used as a simple analogue preamp, it sounds pretty good but not up to the standard of a stand alone $5k preamp.  One might expect that, given all of its features for the price, and again, it is early.  It is very smooth though and nothing sounds unpleasant through it.  It definitely shows promise, we’ll see how further use goes…


I took delivery yesterday and only have about 2 hours on it. As you mentioned it's too early to make a determination. Is there a detailed manual available? There are lots of bells and whistles but aside from a few videos on YouTube there doesn't seem to be a detailed manual. The sound is articulate but pretty thin at this point. My old Rogue RP-1 provides a more full sound. Again, it's early, and I'm sure the M66 will settle in with time. I'm interested in others experience.

@briankwilliams does your volume control click when you spin it or is it completely silent?

I have not seen a detailed manual.  They need one.  Also there’s no software update available on their website yet.  I’m sure that will be coming eventually.  I think the unit sounds good using its internal DAC and streaming Qobuz.  I also have a tube preamp (Primaluna) which does sound a bit fuller, but the NAD sounds good in that mode for a SS preamp (when using its internal DAC).  Mine has about 100 hours on it.  The jury is still out on the preamp running an external source.  

My New Nad M66 won't recognize the connected USB mic that came with it to calibrate.

No, my volume control does not click. That was supposed to be a thing, right? I emailed my dealer today that I was somewhat underwhelmed and the lack of any type of manual was disappointing. He shared my comments with his NAD rep. The rep said they are indeed about to release the software update "soon" and the manual will be released concurrent to the software update. That being said, I believe we have pretty stripped down versions of the M66. That is good as it seems there will be many improvements coming with the software update.

Also I calibrated with DIRAC today and was disappointed with the sound. It thinned the vocals and in general took some meat off the bone. Also, the software in DIRAC seems as though it's in a beta stage. When I go back into DIRAC live processor I get all kinds of errors. I still haven't figured out how to customize or tweak the curves. It's my first experience with DIRAC and with no formal instructions I could be doing something wrong. 

Regarding the mic not working, it's complicated. I had to download the software from the DIRAC site and plug the mic into my laptop, not the M66. You have to download DIRAC live processor. There are simple instructions on the DIRAC website.

Yes, I also had to plug the mic into my laptop, the M66 wouldn’t recognize it.  Brian, wrt the DIRAC curves, did you notice the USB flash drive in the accessory box?  It has a NAD recommended curve on it.  In the DIRAC menu there’s an option to load a curve.  I did that and it sounds pretty good. I assume whatever curve you did use, you loaded it to your M66?  You have to do that step also with the NAD curve.  Also, you may already be aware of this, but if your system already has some room gain in the lower octaves, perhaps even a room gain that is more substantial than ‘neutral’ or flat, DIRAC will flatten that out and result in a perceivable flatter, less bass heavy sound.  Of course you can increase the bass frequencies on that part of the curve, which is one thing the NAD curves do.  They’re boosted slightly in the bass frequencies and gradually decrease as it goes up to 20 kHz.  To tweak the curves you can grab part of it on your screen with the mouse and move it up and down.  
    I also provided my dealer with a whole bunch of input that they said they would pass on to NAD.  If indeed this is a stripped down version, I hope the updates go a long way, because at least as an analogue preamp I’m not super impressed at this point.  My main concern is I am not sure this thing isn’t doing some kind of digital processing no matter what the settings are.  It would be nice to have a switch that just completely defeats the digital side.  I’m not sure that’s possible though based on they way it is designed.

Jimmy, thanks that's great information regarding the NAD curves. I'm going to have to check that out. Like you I'm not impressed by the preamplifier itself. It's just "ok". It does everything ok but isn't that musical. I feel it lacks air and dimension. I love having a one box solution but not sure I'll keep it if it's at the expense of a really good sounding preamplifier.

I agree.  I’m still holding out on it in case I’m missing something or it’s still early.  I also want to make some more comparisons with another preamp.  But otherwise, I’ve come to the conclusion that if this ends up not being a great sounding analogue preamp, that they did not go out of their way to make it so, then one should just buy an M33.  Other than the 4 balanced subwoofer outputs, I’m not seeing what the big difference would be then between the two products.  (Assuming one is using the M23 amp, which I am.  That’s one reason I went out for the M66, I was so impressed with the M23).  

I'm trying to download the curve from the USB but must be missing a step. I see where I can load it into the microphone. But I cannot just load from the hash marks in the top left corner. So does this mean I have to load into the mic and re-test the room? How do I get the NAD curves to integrate with my listening? 

There’s a pretty comprehensive video on NAD’s website about using DIRAC I believe under the FAQ section, you might want to check that out.  But what I did was after finishing my measurements, I went to the DIRAC drop down menu, I think the option was ‘upload curve’ or something like that, then selected the file from the USB drive attached to my computer.  Then I uploaded the curve to the M66.

I'll give it a shot. Another thing I noticed is that the tone controls aren't that responsive. Particularly a hard fade left or right on the balance control doesn't totally silence the opposite speaker. Curious if that's try for you. May be in the update 

Wow after doing the Dirac Live calibration and using the Harmon 8db curve, I'm in Audio heaven. This is well worth the cost for me now. I admit I was kinda worried for a bit. I'm using  2 SVS SB13 Ultra subwoofers and 1 Martin Logan balancedforce 212 with Revel Performa F328be Towers. I can't wait to try Dirac ART when it is available on the M66.

Nice. I didn't see the Harmon curve. I need to spend and afternoon with DIRAC. I don't believe I have it figured out yet. Did watching the video help you have a better understanding? Thanks

I downloaded the Harmon curves elsewhere just google Dirac live Harmon curve. Youthman has them. Yeah I keep going over the video too to learn more. 


Can you hook up a self powered hard drive (2 TB) to the USB input and play WAV files? If so, how do you view the files to play? Do you use a TV hooked up to the M66, or can you see your files on an iPad?

You're supposed to be able to but I think it is not working yet. But it works on my Bluesound node 2 which is same app.

It works.  I just tried a USB unpowered drive, plugged it into the back of the unit.  The M66 automatically indexed it without me doing anything.  About 5 minutes later it became available and playable.  The albums show up in your BluOS app on your tablet, or whatever you’re using.

It works. I just tried a USB unpowered drive, plugged it into the back of the unit. The M66 automatically indexed it without me doing anything. About 5 minutes later it became available and playable. The albums show up in your BluOS app on your tablet, or whatever you’re using.

I only have M12, not M66, but it should be the same either way going through NAD’s BluOS module. You need to go into your BluOS app settings and turn on "Enable Server Mode" and then re-index your music collection - and wait for it to finish! I still had a hell of a time getting it to work with a separately powered USB HDD (traditional hard disk). The re-index process took forever and often didn’t work at all. Since I switched to a Solid State USB drive (2TB, powered through USB), it’s all worked extremely well.

After some more trials using the M66 as an analogue preamp using an external DAC and comparing it to the Primaluna (PL) Evo400 preamp, the PL sounds better.   Besides the usual tube benefits you would expect (3D soundstage and liquidity), the stand alone preamp has more punch, is more dynamic, more ‘raw’ sounding,in a good way.  The NAD isn’t bad at all, but it is refined to a degree that makes it a bit boring.  I do like to listen at lower volumes, and I think that is coming into play in my judgments.  You could turn the NAD up a lot without it losing its cool.  But what is telling is I also prefer the DAC direct to the amplifier (NAD M23) than using the M66.  It is also more dynamic.  So far the M66 sounds best just using its own internal DAC and as a streamer.  I see why the M33 was so well received.  Using the M66/M23 combo just as a digital streamer/pre and amp basically replicates the M33, and it sounds very good.  Overall I think the M66 is a great product and does a lot very well.  


Thanks for your impressions - and that’s a bit of a bummer. I was a little interested in M66 as a pure 2ch analog preamp, but that’s not gonna cut it at almost $6K. With the analogous "older" pairing, M22 V2 and M12, I also found the preamp (M12) to be the weak link in an "analog 2ch" context. M12 preamp is just a boring, sterile sound compared to a good tube preamp. It’s easily outclassed by its partner M22 power amp (either v1 or v2, really), which absolutely shines with a good tube pre.

I even paired the M22 v2 for a time with a VAC Master, which is a little crazy ($30K tube pre), but worked shockingly well. M12 gets left in the dust :( I do enjoy the M12 for movies and more casual digital streaming, though.

There are a ton of analog preamps out there. To me this NAD M66 is about all the digital features dirac live, Bass control and someday Dirac ART. The top of the line ESS Dac helps.

I agree. It really is about the digital capabilities. I have a blu sound vault with hundreds of CDs stored and it integrated seamlessly with the M66 over the network which was great. My problem is that I have a very good and expensive power amplifier and hate to settle on the less dynamic sound of the NAD M66 for the features alone. I've got a tough decision to make as to whether I should keep it out not. 

Brian to me the dynamics that dirac live custom curves is what I have loved the loved the most. The bass is so smooth now. I use to have huge bass peaks and dips which made it so didn't like certain songs. I honestly can't wait for Dirac live ARTafter hearing the improvement from bass control. Now I want dirac live in my other stereo rooms in my house. 

To all the owners of M66. I have seen the meters function in white. Can you change the color to other choices?

You cannot change the meter colors at this time. Though there is also a digital meter function that looks like the old 80s type horizontal meters.

There’s a product manual available now on the M66 page of the NAD website.  I was able to get to use about 60-70% of the features listed in the manual, without a manual, so you can tell the product is pretty intuitive in use, for all that it does.  I haven’t tried things like Bluetooth or E-arc.

I received my M66 a week or so ago. It sounds good so far but I too have a smooth volume control, no steps or clicks when turned.

I tried the e-arc hdmi connection, got no output, but a humming noise did produce, not sure what's going on there, bought a new cable and am going to try again tomorrow. Glad a manual has shown up..


jarogers make sure the earc on your TV is outputting PCM cause the NAD won't read dolby or dts. 

Yes thanks for that, I am looking into that, can't find where that is on my TV at the moment. Need to dig deeper.. I hope it's a simple setting and nothing more..

I heard back from my dealer who heard back from NAD.  WRT the resistor ladder volume control, they said some companies choose to have theirs ‘click’ but ultimately NAD thought some customers might not like it so they deliberately silenced it.  Fair enough…