Review and Measurements of NAD T758 V3 AVR

[amirm]

Did you test with speakers connected and disconnected, like with the Pioneer?

I did. Should have noted that. It shut down with the speakers connected at 0 dB and 2 volt input when I was testing the DAC.

So to be clear, all DAC measurements are with speakers *disconnected*.

 

[amirm]

ure, testing it properly requires at least 7 dummy loads, but what is the point testing a multichannel AVR as a 2ch stereo amplifier? That's not what people are buying is it?

With surround content, rear, side and height channels are doing next to nothing 99% of the time. It is the Left, plus right and especially the center channel that do all the work. I should be testing three channels to approximate the workload.

But 2-channel testing is also useful as we compare to dedicated amplifiers.

 

[restorer-john]

But 2-channel testing is also useful as we compare to dedicated amplifiers.

Yes, I agree.

 

[audioBliss]

Well, well, well. I'm actually not surprised at all. This is a very useful review I have to say. I'm even more interested in Anthem and Arcam units. Let's see if any manufacturer has a good AVR. Imo there was a bit to be gained with separate DAC with my Arcam so I'm guessing it doesn't measure quite reference either. But I would be surprised if it's as bad as this.

 

[speedy]

It would be really interesting to reach out to the PR & Support departments at these companies as these AVRs are researched/tested to see if those companies want to make an official public statement.

For example, I wonder if NAD might say something like, "please test our higher end unit because...", or if they might claim that the unit is defective and send you another.

I used to own this receiver and returned it because of HDMI ARC/CEC issues, but I personally found it to be an excellent sounding receiver so these results are surprising to say the least.

Really looking forward to more tests like this.

 

[audioBliss]

Looking for images of inside I found this comment:

https://www.audiosciencereview.com/...buck-for-avr-with-pre-output.2387/post-105623

by Kal Rubinson


Maybe your AVR has something wrong. I can not believe the first measurement, although I could not with the TotalDac, so I fear the worst: the problem is generated by NAD and maybe cheap ensamblers? It is an incredible bad measure.

Nah I'm not surprised. I've listened to a lot of NAD stuff and it has not sounded good to me. Only one product has sounded descent and that's the NAD 208 THX power amp but that's a really hit and miss amp. Some units are good many are not.

 

[amirm]

It would be really interesting to reach out to the PR & Support departments at these companies as these AVRs are researched/tested to see if those companies want to make an official public statement.

I sent my Pioneer AVR review to my contact there. He didn't even reply to my message.

 

[amirm]

I just sent a link to the review to NAD support. Will report back if I hear anything.

 

[audimus]

I just sent a link to the review to NAD support. Will report back if I hear anything.

Highly likely, you will not hear anything or at best get a generic statement.

But, I bet it will get noticed and discussed inside and hopefully lead to some different engineering decisions for v4! That is the best contribution of this site.

 

[Sal1950]

Nah I'm not surprised. I've listened to a lot of NAD stuff and it has not sounded good to me. Only one product has sounded descent and that's the NAD 208 THX power amp but that's a really hit and miss amp. Some units are good many are not.

The audibility of these failings is highly debatable , much more likely are expectation bias that leads you to make these various conclusions. It would take direct A/B evaluations under tightly controlled, level matched conditions to come up with any supportable data.
That's not to say these measurements are without value and if examined closely could lead to advances in the SOTA.
Personally I find it disturbing that these units have revealed such a disrespect in the design of parameters that should be easy-peasy to execute in a much more respectable manner. Its a lowest common denominator attitude in R&D of much of todays units.
But before you stereo snobs turn up your noses and point fingers, look at how many very simple 2 channel devices have also turned in very poor showings, cheap DAC's and amps of which have been the worse offenders. The only reason for the exteme failings we have seen in the AVR's is manufacturers attempt of pack in so much, at such a low cost.
Amir, I encourage you to do your best submitting your results to manufacturers ala Atkinsons Manufacturer's Comments. I believe they figure no one is looking into such things and their secrets are safe. NOT.

 

[amirm]

It would help if members contacted them too. It my have more weight than me doing it.

 

[Dogen]

...Amir, I encourage you to do your best submitting your results to manufacturers ala Atkinsons Manufacturer's Comments. I believe they figure no one is looking into such things and their secrets are safe. NOT.

Excellent idea. I think ASR is getting a high enough profile that we might get some responses. BTW, my ignorant opinion is that these measure so badly due more to laziness and negligence than cost-cutting. They’re put together slapdash by designers incented only to deliver a list of features. It wouldn’t be surprised if these went out the door with NO comprehensive testing.

Yes, AVRs are more complex and there are more channels and features, and more licensing to be paid, but I would imagine there have been technical advances that offset some of the increased cost of manufacture.

 

[DownUnderGazza]

Given the startling bang-for-buck of active monitors such as the JBL LSR305, I wonder if we should instead be encouraging manufacturers to revive their PrePro offerings instead? Strip out some of the excess such as poor quality amps and instead support XLR outputs!

If such as the Emotiva MC-700 (https://emotiva.com/collections/processors/products/mc-700) had XLR outputs, and it measured ‘ok’, it could offer a great alternative...

 

[Rja4000]

@amirm
In you description, you say "The NAD T758 comes with Direct Lite room equalization"
Isn't that "Dirac Live", instead?

 

[audimus]

@amirm
In you description, you say "The NAD T758 comes with Direct Lite room equalization"
Isn't that "Dirac Live", instead?

No, it is a lite version. You can upgrade to the full version for $100.

 

[Rja4000]

No, it is a lite version. You can upgrade to the full version for $100.

But that's still Dirac and not Direct, isn't it?
The light version, as far as I understand, only corrects below 200Hz.

 

[Rja4000]

Those boxes are quite complex.
I'm still wondering if there is not some DSP processing in the audio chain.
The fact that it resamples to 96kHz seems to indicate that.
And it looks like to force "Direct" mode is not so straightforward. I had a look at the manual, and in page 24, they describe how to get stereo "without surround enhancement". But I guess you checked that.

Would there be a way to check if a DSP is in the loop and what it's doing if that's the case ?
I can't think of a measurement for that, though.
I wonder what the impact of "surround ennhacement", or Dirac correction would be on measurement. Any idea?

Thinking again, the presence of a "surround" processor in the "stereo" inputs loop could maybe also explain why we see much better performance from the 7.1 Analog input. Because, of course, this makes no sense to add such processing on those.

 

[amirm]

But that's still Dirac and not Direct, isn't it?

It is. I just corrected the review.

 

[amirm]

Would there be a way to check if a DSP is in the loop and what it's doing if that's the case ?
I can't think of a measurement for that, though.

I have turned off processing as you can tell from flat frequency response. I see nothing else that can optimize it more. They don't have a way to bypass things. They set the parameters to neutral it seems and keep the DSP pipeline going.

 

[Rja4000]

I have turned off processing as you can tell from flat frequency response. I see nothing else that can optimize it more. They don't have a way to bypass things. They set the parameters to neutral it seems and keep the DSP pipeline going.

Thanks. I had no doubt you did check.
Just that there could be a hidden trick.
Looks like this DSP is adding a ton of unwanted things to your poor signal.

I wish Dirac is coming with a 192kHz or 384kHz implementation some day.
Dirac is quite excellent as a correction system, in my opinion.

Makes me think: I will have a look at how my miniDsp Dirac behaves in "flat" mode, when I can find some time.