NAD M33 Streaming Amplifier Review

[gvl]

You can't just decide to go to Hawaii. You have to quarantine for 14 days or take COVID test. With NAD, you can go online and buy it now!

I can't fault this

 

[watchnerd]

This or a family vacation in Hawaii?

Our initial budget for our last vacation in Hawaii was $5k.

But we came back having spent $7k.

Darn submarine rides....

 

[TomJ]

... that price I can buy two genelec 8341 ...

I wonder what we'd find if we measured the electronics of active monitors the way we measure external components...

 

[vkvedam]

A bit disappointed in all honesty, Linn did much better IIRC

 

[restorer-john]

Hard to tell if it is a universal issue or just this one. Will have to test another to be sure. Maybe the owner can contact NAD and ask them if this is to spec and see what they say (I know, it is a long shot).

There have been a number of amplifiers you've tested recently with the same issue- I am wondering if there's a non-linearity in one of your dummy loads/connections or the connections to the AP?

Can you run the tests again and swap the channels? ie, does it follow the loads/AP channel?

 

[YSC]

I wonder what we'd find if we measured the electronics of active monitors the way we measure external components...

Well likely they are worse, but the main difference is that for active stuffs they did considered the electronics inside to be not affecting the output from the drivers and the active component likely only work for a narrow band at limited and best performing part of it. While external stuffs need to be able to drive all passive stuffs out there and still performs well at every bandwidth and power combination to make it able to perform at the same level of active speakers so it’s reasonable to be a lot tougher in required performance

 

[amirm]

There have been a number of amplifiers you've tested recently with the same issue- I am wondering if there's a non-linearity in one of your dummy loads/connections or the connections to the AP?

Can you run the tests again and swap the channels? ie, does it follow the loads/AP channel?

I packed the unit already. This does happen occasionally if the connectors are not very tight. I checked for this and didn't change the results. I think often one amp is disadvantaged with respect power path and such.

 

[ririt]

Here's mine. Same functionality, better SINAD. More boxes.

NAD stole my idea. View attachment 91759

Your initial idea is less expensive and should deliver better measurements at the cost of the overall design and of the bigger footprint

 

[da Choge]

Thank You, Amir - Great Job! I've been looking forward to this review for quite some time. This is a beautiful unit with great design and functionality, but slightly disappointing results considering some of its primary components (Purifi & ESS). However, after previously reading Stereophile's measurements, I was actually expecting a little worse when it finally got to ASR, so not too disappointed.

As much as I wanted to love this unit, for my interest, there are two deficiencies of some concern: 1) no current Roon compatibility (NAD has indicated it will eventually get there, but NAD always takes its time, and sometimes never really gets the software just right -- so, I wouldn't consider buying this until it was officially Roon Certified and proven) and 2) no actual Home Theater Bypass mode/inputs. I understand why this may have not been included in the design of the M33 with the mandatory AD conversion of its analog inputs to allow for Dirac processing, but at $5000, I think NAD could have managed an analog unity-gain pass-through mode to its Purifi amp stage. The way the analog inputs are designed, it may not pose as much of a volume matching challenge as a time alignment challenge (audio time delays) with the video stream and other audio channels of an AVR. I am very sensitve to such time issues, and I would be very interested in anyone's comments and evaluations in using this unit's stereo channels in conjunction with their AVR (as the front channel amplifier either for multichannel music or for HT audio-video use).

Still, was very happy to see this ASR review. Again, thanks to Amir and to the forum member who sent it in for review !!!

 

[Joachim Herbert]

Schade.

 

[Veri]

That multi-tone looks really good to me, really :O

Also, the analog->digitised dashboard is hardly worse than the digital input, which means the ADC used is a fairly high quality one

 

[polmuaddib]

I don't agree that this unit is compared to AVR/AVPs. I get that they are similar in some ways, but their use is different and AVR/AVPs still have more codecs and pathways, HDMI splitters and whatnot...
And in the end this is a lifestyle unit. Like the ones B&O used to make (probably still, but i don't follow) and should be in a category of its own. And these All-in-one units are on the rise. So, we can expect more to fill the chart.

 

[Vasr]

2) no actual Home Theater Bypass mode/inputs. I understand why this may have not been included in the design of the M33 with the mandatory AD conversion of its analog inputs to allow for Dirac processing, but at $5000, I think NAD could have managed an analog unity pass-through mode to its Purifi amp stage. The way the analog inputs are designed, it may not pose as much of a volume matching challenge as a time alignment challenge (audio time delays) with the video stream and other audio channels of an AVR.

This is a good point. However, I think volume management while it can be done wouldn't be convenient to use in practice while time delay is a non-issue. This is not conceptually different from using a pair of powered speakers for your HT system. So, any feature in your HT system to do time alignment will take care of any delays within the NAD (with or without Dirac engaged as long as you always use the mode that was used to measure it with the HT system).

But without a HT bypass at unity gain and also bypassing any processing (that will make it look like a clean external amp to your HT system), you have a couple of caveats:

1. The volume level on the NAD to use. In theory, you can put the NAD volume at 0db and use the HT volume control to control the volume so you have the complete dynamic range available. But this is a bit dangerous potentially unless you have an automatic volume change on switching the source. It is also inconvenient to change the volume to what you need on the NAD for the calibration done for HT every time you switch to HT from another source. If it allows you to specify a volume to start at whenever you switch to a specific input, then this becomes a non-issue. I have not seen the manual to see if it does. In this case, you can set the volume to whatever gets it closest to the volumes on the HT for other channels and then let the HT fine-tune its pre-out volume to match. The volume control on the HT system will then control all channels during use.

2. Engaging or disengaging Dirac. You can have Dirac engaged and then do the HT room EQ, so it will be doing the EQ over the Dirac corrected curve. If you don't and then use Dirac for other sources you will have to switch it off before using HT every-time unless this can also be specified as a per source setting. But this is cleaner and will work correctly with any crossed over sub in your HT system. If you engage Dirac with HT, then would need a separate profile setting for HT for the crossed over setting from the HT coming into your amp to have different correction than using another source into it for the full range.

So, while technically feasible, usability may not be as simple as a single remote click switch between HT and local sources.

 

[Wombat]

NAD seem to add a very hefty price premium for the word digital.

 

[Alexanderc]

@amirm how concerned should we be about the difference in channel performance? That seemed much worse than I recall seeing in other amplifiers or integrated products and not the norm. Is that a manufacturing defect or variation of some kind?

There is a channel mismatch in the Stereophile measurements as well, FWIW. https://www.stereophile.com/content...3-streaming-integrated-amplifier-measurements

 

[Soniclife]

Different situations. In DAC testing the volume is set to -6 dB which means the amps are running at full power. In sharp contrast, the amplifier test is done at just 5 watts so the amp is not remotely stressed. Is this what were asking?

Probably, this will be part of the rising curve on the power sweeps.

 

[FrantzM]

Here's mine. Same functionality, better SINAD. More boxes.

NAD stole my idea. View attachment 91759

I can only name 2 of the boxes. What are the others and their approximative specs?

 

[Haskil]

Amir, merci pour ce test. QUESTION: pourquoi n'utilisez-vous pas Audirvana en plus de Roon: cet excellent logiciel de lecture vous permettrait de tester le streaming 24 bits ... ce logiciel est peu coûteux.

 

[restorer-john]

I checked for this and didn't change the results.

Perfect. I'd just noticed a few amps with similar plots recently and figured you'd be all over it.

 

[restorer-john]

There is a channel mismatch in the Stereophile measurements as well, FWIW. https://www.stereophile.com/content...3-streaming-integrated-amplifier-measurements

Thanks for posting that. Great to see correlation.