NAD M28 Seven Channel Power Amplifier Review

[CDMC]

Indeed and it also depends on the rest of the setup. Purify is a big improvement over Ncore. Next to this, I allways wonder how objective is the person who does the measurements. Are there more tests who have the same outcome ? Is it a controlled environment ?

Actually Purifi is not a big improvement. It is the next evolution of the hypex design with improved measurements. The improvements on the best day, with the best equipment, the best sources, quietest room, and perfect hearing, may possibly be slightly audible in some cases.

In the implementation by NAD, the M28 has worse measurements than the M27. You said you wanted more power for your speakers, the M28 puts out less, but only about 1db.

There is nothing wrong with purchasing the latest and “greatest” because you want it, but please don’t make excuses or play games (i.e. the measurements may be biased or rigged) to justify your purchase. Doing so just makes you look bad and wastes everybody’s time. If you want to do a level matched, blind test between the two, we welcome that. If you want to wax poetically about imaginary PRAT differences and how your system has been transformed, there are many other forums that enjoy those discussions and you will get the feedback you want.

 

[rkwinkel]

I do not need to justify the purchase, but because I question the validation of these measurements, does not mean I play games. I am true believer of measurements, but validity is just as important as measurements it self. It would help if more tests were done and there were a comparison between the different test results. If these results align than I would say this is a valid measurement. I am not saying that his measurements are wrong, I am just missing validation of the results. At this stage it is just a measurement of one person. Just my two cents. It would be nice if NAD could confirm these measurements and give a explanation for these variances. Does NAD know about these results ?

 

[voodooless]

I have no idea. It is an anecdotal statement based on my experience with the M27 a few years back and my recent experience with the M28. Make of it what you will!

So you’re basing all of this on two instances years apart?

 

[voodooless]

At this stage it is just a measurement of one person. Just my two cents.

Measurements are not subjective. You’re now treating measurements as if they were subjective opinions. They are not! We don’t need more measurements, the measurements system is top notch and industry standard and the method is very precise and repeatable, resulting in measurements that are directly comparable to each other.

 

[CDMC]

I do not need to justify the purchase, but because I question the validation of these measurements, does not mean I play games. I am true believer of measurements, but validity is just as important as measurements it self. It would help if more tests were done and there were a comparison between the different test results. If these results align than I would say this is a valid measurement. I am not saying that his measurements are wrong, I am just missing validation of the results. At this stage it is just a measurement of one person. Just my two cents. It would be nice if NAD could confirm these measurements and give a explanation for these variances. Does NAD know about these results ?

But that is not what you are doing. You are attempt to cast doubt without any basis. It is no different than when someone says: "I hear that such and such is having an affair". Here the measurements, which were made by the same person, with the same equipment, show the M28 doesn't perform as well as the M27. This is not the first time in audio a newer product doesn't perform better than an older product.

So the short question is, do you have any basis to question the measurements, or are you just trying to sow doubt (I believe the current hot term is FUD, fear, uncertainty, and doubt)? It appears the more that you post that you are just trolling.

 

[CDMC]

So you’re basing all of this on two instances years apart?

Just my thoughts. Maybe give Kal a bit of latitude. His contributions are valuable and he is a subjectivist who is clear when he expresses his views whether they are based on his subjective view or objective measurements. I for one would hate to see him stop posting here because his views, which are expressed in a polite and clear manner may disagree with others. Any good intellectual endeavor involves looking at all sides of the argument, even those we don't agree with or question.

 

[Casey Leedom]

So I have this same mostly pointless conversation with my friend who’s an unabashed Subjectivist. He says, ”Measurements aren’t capturing everything”. And I usually reply, yes, that’s quite possible. So let’s A. Do a Double Blind test to verify that there may indeed be some data which we’re not capturing in the current set of measurements but Humans can hear, B. If we do find that a Human can consistently distinguish between two things X and Y, then start trying to figure out what we’re not currently measuring that Humans can detect. As a scientist, I’m always prepared and open to new Data which points to currently unexplained phenomena. (This, by the way, is why the field of High Energy Particle Physics has been languishing for the last 40 years: a dearth of new unexplained data.)

I finally got a chance to unbox the NAD M28 on Saturday night with that same friend and he immediately claimed that it sounded a lot better than my old Emotiva MPS-1 (Class H, 7 x Monoblock implementation from 2007), and he demanded that I acknowledge that. But truth to be told, I couldn’t say either way: my Audio Memory just isn’t good enough and there was no easy way to do a true, Level-Matched A/B Comparison.

If someone held a gun against my head I might say that the bass seemed a bit tighter and more distinct (less muddy/congested?) ... maybe a higher Damping Factor? ... but I wouldn’t swear on this “difference” because of the aforementioned lack of Level-Matched A/B Comparison.

But say, we had been able to do those Level-Matched A/B Comparisons and I had been able to successfully distinguish between the two Amplifiers significantly better than 50%. First, we’d need to measure my MPS-1 in exactly the same way. If it measured significantly differently, then we’d need to form a testable hypothesis about what aspects of these different measurements I might be hearing. And if it measured the same, then we’d have to form testable hypotheses on what we might not be measuring.

So in the end of the game, if a human can distinguish between two things X/Y but our current measurement protocol doesn’t see a difference between X/Y, then we need to start trying to figure out what we haven’t been measuring. The funky wet-ware that we’re made of is wonderful, but it’s not capable of attosecond resolution, etc.

Casey

 

[Kal Rubinson]

You still owe the M28 ?

Own? Yes.

 

[rkwinkel]

But that is not what you are doing. You are attempt to cast doubt without any basis. It is no different than when someone says: "I hear that such and such is having an affair". Here the measurements, which were made by the same person, with the same equipment, show the M28 doesn't perform as well as the M27. This is not the first time in audio a newer product doesn't perform better than an older product.

So the short question is, do you have any basis to question the measurements, or are you just trying to sow doubt (I believe the current hot term is FUD, fear, uncertainty, and doubt)? It appears the more that you post that you are just trolling.

Why would I troll ? I take measurements very seriously. I believe in data driven decission makinig. I wonder why you question my intentions, while I make a valid point about validation. When i read measurements I allways look at reliabilty of the data. I am not saying what he measured is wrong, I am just saying to draw a conclusion based only on this measurement is simply not correct. More testing would be needed and outcomes should be compared. And off course measurement can be subjectively interpretated. Anyway we do not have to agree and lets agree to disagree.

 

[Casey Leedom]

Hhmmm, I will mention one big negative on the NAD M28: The three-year warrantee is non-transferable. So its value in resale drops like a rock the second you take possession of it ...

Casey

 

[CDMC]

Why would I troll ? I take measurements very seriously. I believe in data driven decission makinig. I wonder why you question my intentions, while I make a valid point about validation. When i read measurements I allways look at reliabilty of the data. I am not saying what he measured is wrong, I am just saying to draw a conclusion based only on this measurement is simply not correct. More testing would be needed and outcomes should be compared. And off course measurement can be subjectively interpretated. Anyway we do not have to agree and lets agree to disagree.

Let me take you back to what you originally said: "I ordered the M28. I will compare it to the M27. The main reason is that the M28 has more power, which will benefit my Dyns. Also I read a lot of good things about Purify.. "

I pointed out, that in fact that M28 has less power. You then started to argue that the measurements may not be reliable. As I have pointed out, the measurements were performed by the same person, using the same equipment, there is nothing to question about them. These aren't people where you put them on a treadmill and they perform differently each time, the equipment performs the same each time.

I will again ask, aside from your attempts to cast baseless doubt on the measurements taken by Amir, please provide some support for your position that a conclusion about data cannot be based on only one (set of) measurement (noting that it is not one measurement, but a comprehensive set of measurements)?

What it looks like is that when the objective data disagreed with your claim for the purchase being the "main reason is that the M28 has more power", you decided to question the data rather than your stated reason. Again, there is nothing wrong with purchasing something that you want or liking to own the latest model. The issue arises when you make a claim, that is not objectively correct and when confronted then engage in trying to discrete objective data. That is not good science and doesn't belong here.

 

[CDMC]

So I have this same mostly pointless conversation with my friend who’s an unabashed Subjectivist. He says, ”Measurements aren’t capturing everything”. And I usually reply, yes, that’s quite possible. So let’s A. Do a Double Blind test to verify that there may indeed be some data which we’re not capturing in the current set of measurements but Humans can hear, B. If we do find that a Human can consistently distinguish between two things X and Y, then start trying to figure out what we’re not currently measuring that Humans can detect. As a scientist, I’m always prepared and open to new Data which points to currently unexplained phenomena. (This, by the way, is why the field of High Energy Particle Physics has been languishing for the last 40 years: a dearth of new unexplained data.)

I finally got a chance to unbox the NAD M28 on Saturday night with that same friend and he immediately claimed that it sounded a lot better than my old Emotiva MPS-1 (Class H, 7 x Monoblock implementation from 2007), and he demanded that I acknowledge that. But truth to be told, I couldn’t say either way: my Audio Memory just isn’t good enough and there was no easy way to do a true, Level-Matched A/B Comparison.

If someone held a gun against my head I might say that the bass seemed a bit tighter and more distinct (less muddy/congested?) ... maybe a higher Damping Factor? ... but I wouldn’t swear on this “difference” because of the aforementioned lack of Level-Matched A/B Comparison.

But say, we had been able to do those Level-Matched A/B Comparisons and I had been able to successfully distinguish between the two Amplifiers significantly better than 50%. First, we’d need to measure my MPS-1 in exactly the same way. If it measured significantly differently, then we’d need to form a testable hypothesis about what aspects of these different measurements I might be hearing. And if it measured the same, then we’d have to form testable hypotheses on what we might not be measuring.

So in the end of the game, if a human can distinguish between two things X/Y but our current measurement protocol doesn’t see a difference between X/Y, then we need to start trying to figure out what we haven’t been measuring. The funky wet-ware that we’re made of is wonderful, but it’s not capable of attosecond resolution, etc.

Casey

As humans we are great at fooling ourselves, even when we try not to. I went through it recently. Purchased a RME DAC/Pre to replace my Schiit Freya S and Gungnir MB. When I hooked it up, something sounded wrong with it, way off. I switched back and forth and something wasn't right. I ran the RME bit test and it showed it was working correctly.

I then took the RME and ran it into my Freya S and level matched it within 1 db of the Gungnir MB. I could then switch back and forth between each instantly with the Freya remote. Guess what, they now sounded identical. There were a few things that I thought sounded slightly different, but when I would play the same section of music over again back to back with each, I couldn't put my finger on what might be different and couldn't reliably hear a difference. Keep in mind, this was not done blindly, but just by level matching and being able to switch back and forth instantaneously without the 1 minute pause of switching connections.

 

[Casey Leedom]

@Kal Rubinson, I gather that you also have the NAD M28. Stupid question (which isn’t covered in the M28 online manual): What are the specifications for the male 12V Trigger input? What kind of plug is it and how should it be wired? This plug wasn’t included with my M28.

Casey

 

[Kal Rubinson]

I just pulled out a mono 3.5mm cable, connected it to my Marantz AV8805 and it works. Marantz' limits are 12 V DC/150 mA.

 

[Casey Leedom]

Thanks @Kal Rubinson!

Casey

 

[TomJ]

Wondering the same about the new C 298. Spec sheet states the same input impedance on XLR and RCA....

Update from NAD support re the C 298 buffer question: fully balanced, both inputs have the same Ω because each has its own buffer.

 

[zachery2006]

Measurements are not subjective. You’re now treating measurements as if they were subjective opinions. They are not! We don’t need more measurements, the measurements system is top notch and industry standard and the method is very precise and repeatable, resulting in measurements that are directly comparable to each other.

Somewhat disagree. Mathematician here. Yes, measurement is not subject, but it is not exactly deterministic as well. It is not like 1+1 must be 2 thing. Scientifically or statistically speaking, we need more samples to derive a conclusion. But in reality, people usually don’t do that.

For me, I could ignore the measurements difference between M27 and M28. I’m more curious to know how they sound differently. Cuz I don’t have either Ncore or Purifi. Is there any characteristics between each?

I got a chance to use my store credit to buy a M28, so I only need to pay $4000USD. I do consider to buy one. The pain point is I mostly use it for music(stereo). Does NAD plan to update M22 V2 in the near future?

 

[Kal Rubinson]

Does NAD plan to update M22 V2 in the near future?

Perhaps but how will they differentiate it from the C298?

 

[zachery2006]

Perhaps but how will they differentiate it from the C298?

Oh, yeah. C298 is using more affordable material with same core components as M series. The only thing to me that C298 missing is the auto standby function. This pushes me towards M28. Do you distinguish any sound difference between Ncore and Purifi module?

 

[TomJ]

Perhaps but how will they differentiate it from the C298?

Good question, who knows. They could add an OLED screen that displays power meters, and even the amp operating state by polling the I2C registers in SW mode with a micro. Note the ARM micro in the C 298. They could also replace or augment the C 298 USB service connector with a LAN interface for diagnostics readout like Krell and others.