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Review and Measurements of NAD T758 V3 AVR

iflyadesk

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Yes, but Amir didn’t measure noise floor - he measured SINAD. The -53dB 3rd harmonic he shows only exists in the presence of a full scale signal.

Am I misunderstanding the following statement?
Notice that even at this lowered volume, we have issues with noise. The FFT noise floor is quite high and SINAD is determined by that, rather than distortion products. A problem that we see when we measure its dynamic range:
 
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Yes, but Amir didn’t measure noise floor - he measured SINAD. The -53dB 3rd harmonic he shows only exists in the presence of a full scale signal.
For the laymen, he's saying that amir's testing only shows up when the receiver is at 0db on the volume scale. When you dial back to -6dB the SNR is much more tolerable.

If you hear noise as soon as you hook things up, that's either a problem with the wiring somewhere or a defective unit. My unit does not produce noise until about -15dB and even then, you can't hear it at the MLP.
 

Theriverlethe

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For the laymen, he's saying that amir's testing only shows up when the receiver is at 0db on the volume scale. When you dial back to -6dB the SNR is much more tolerable.

If you hear noise as soon as you hook things up, that's either a problem with the wiring somewhere or a defective unit. My unit does not produce noise until about -15dB and even then, you can't hear it at the MLP.
No, I’m saying the kind of distortion Amir measured only exists along side an input signal. Volume setting is irrelevant. This Sound & Vision measurement claims SNR to be around 94dBA with an 8 ohm load:

https://www.soundandvision.com/content/nad-t758-v3-av-receiver-review-test-bench

Preamp outputs should be better, but that’s still pretty good.
 

Sal1950

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I run Genelec 8010a satellites and SVS SB-1000 subs. As soon as I turned it on the noise was audible and unbearable. Changing any setting (like switching source, adjusting surround mode) produces scratching and popping sounds like a record player.
I tend to agree with theeriverleth that something was defective in the NAD. Nothing I can thing of in the noise measurements would cause the noise when switching sources or modes? In any case you have returned it. All I can say is my speakers are fairly high sensitivity (92 dB/1m/2.83V rms, half space) and with my Marantz 7703 and Adcom amps I can put my ear right to the speaker and hear no noise or hum to speak of.
 
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No, I’m saying the kind of distortion Amir measured only exists along side an input signal. Volume setting is irrelevant. This Sound & Vision measurement claims SNR to be around 94dBA with an 8 ohm load:

https://www.soundandvision.com/content/nad-t758-v3-av-receiver-review-test-bench

Preamp outputs should be better, but that’s still pretty good.
My comment implies an input signal... Volume setting is very relevant since Amir had the volumes at 0dB and -6dB respectively to get his measurements at 2V and 1V.

We are saying the same thing, I am simply translating from geek to "what's the screen say?"
 

Theriverlethe

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My comment implies an input signal... Volume setting is very relevant since Amir had the volumes at 0dB and -6dB respectively to get his measurements at 2V and 1V.

We are saying the same thing, I am simply translating from geek to "what's the screen say?"
Okay... The post I was responding to didn't seem to imply an input signal.
 
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Hello!
I've purchased the nad 758 v3 mostly because i got a 1000$ price on it, new. Other options like denon/marantz were far too expensive, the 3500h was 900$.. ok, now that we got that out of the way.. im just a casual listener with little to no experience. I also bought the buchardts s400 as fronts and i have a question regarding an external amp. I would like to give them more power. Ive taken the cambridge cxa60 from my father to test but it didnt work out that great. Ive connected the nad and the cambridge via rca cables from nads pre outs, speakers connected to the cambridge and it worked! But there was a very audible hissing noise coming from the speakers. When i went over half the way with the volume on the cambridge the hissing was getting worse and worse.
Now, i dont believe i did something wrong but i still want to add some extra power to the buchardts, was thinking about 150-200 watts. What do i need? An integrated or a power amplifier? Using the pre outs, will it use the dac in the nad or in the integrated amplifier, if it uses the dac in the nad then clearly all i need is a power amplifier but.. i dont know. Is the hissing coming from the nads pre outs so adding external amp is out of the question for this unit? I am very sorry for these silly questions, if you consider my post too low quality, just delete it. Thank you
 

Bear123

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Hello!
I've purchased the nad 758 v3 mostly because i got a 1000$ price on it, new. Other options like denon/marantz were far too expensive, the 3500h was 900$.. ok, now that we got that out of the way.. im just a casual listener with little to no experience. I also bought the buchardts s400 as fronts and i have a question regarding an external amp. I would like to give them more power. Ive taken the cambridge cxa60 from my father to test but it didnt work out that great. Ive connected the nad and the cambridge via rca cables from nads pre outs, speakers connected to the cambridge and it worked! But there was a very audible hissing noise coming from the speakers. When i went over half the way with the volume on the cambridge the hissing was getting worse and worse.
Now, i dont believe i did something wrong but i still want to add some extra power to the buchardts, was thinking about 150-200 watts. What do i need? An integrated or a power amplifier? Using the pre outs, will it use the dac in the nad or in the integrated amplifier, if it uses the dac in the nad then clearly all i need is a power amplifier but.. i dont know. Is the hissing coming from the nads pre outs so adding external amp is out of the question for this unit? I am very sorry for these silly questions, if you consider my post too low quality, just delete it. Thank you
Well the NAD did measure rather poorly but at moderate volumes I don't think it was nearly as bad. Maybe try going straight from the NAD to the speakers to see if you still have the hiss? Eliminate the Cambridge as the source of noise. Someone can correct me if I'm wrong, but if you don't get hiss from the NAD itself, I think you will want to ensure that if you do go with external amplification for more power, you will want to make sure to get one that can be fully powered with low voltage since the NAD is crapping the bed by 2 volts. Hopefully Amir or someone with more knowledge on the subject will chime in if this would work or not.
 
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Hello Bear123 and thank you for your kind reply! Speakers are connected to the nad and i get no hiss. However, i noticed while playing some bass heavy tracks at high volumes (~ -10db in stereo mode, no sub, speakers set to large) it clips on some bass tones. I think its clipping and i do not believe the buchardts are to blame, its not "that" loud really. It sounds like an "oomph", like the woofer is hitting a wall. Or maybe thats the maximum for the speakers? That would be really disappointing :(.
For movies, im ok with the receiver and after a lot of tweaking with dirac it sounds reasonably well for my not so ideal living room so as far as movies go, im ok with it. Im also using 2 opposite subwoofers and i managed to get as even as possible bass response in my room using dirac and test tones.
Everything works as expected with the nad but i wanted to also see how the buchardts would perform in stereo only with a better amp+dac and run them without subwoofers. Actually, my room helps the buchardts to easily hit 30hz and with more power i figured i could have a better music experience as well as removing the subs.
 

Bear123

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Hello Bear123 and thank you for your kind reply! Speakers are connected to the nad and i get no hiss. However, i noticed while playing some bass heavy tracks at high volumes (~ -10db in stereo mode, no sub, speakers set to large) it clips on some bass tones. I think its clipping and i do not believe the buchardts are to blame, its not "that" loud really. It sounds like an "oomph", like the woofer is hitting a wall. Or maybe thats the maximum for the speakers? That would be really disappointing :(.
For movies, im ok with the receiver and after a lot of tweaking with dirac it sounds reasonably well for my not so ideal living room so as far as movies go, im ok with it. Im also using 2 opposite subwoofers and i managed to get as even as possible bass response in my room using dirac and test tones.
Everything works as expected with the nad but i wanted to also see how the buchardts would perform in stereo only with a better amp+dac and run them without subwoofers. Actually, my room helps the buchardts to easily hit 30hz and with more power i figured i could have a better music experience as well as removing the subs.
The NAD is fairly low on power so a stronger amp may help out some with the Buchardt's. However, sound quality and fidelity will be better when bass managed with well set up dual subs, so I see no reason to listen to music without them, honestly. Regardless, a better amp may help matters some....but since the NAD clips above -6, I'm still guessing it may make sense to make sure that if you get an external amp, it should be one that can be driven fully with a low pre-out voltage signal. Again, I hope someone else will comment on whether this would or would not be better than an amp that requires a full 2 volts to drive. For example, the Monolith amp tested on Audioholics delivered full rated power with 1.43 volts....200 watts into 8 ohms and 300 or so into 4 ohms. Should be plenty for your Buchardts and the Monolith seem quite reasonably priced and a good warranty.

Are you wanting to remove the subs from your system? Or just seeing what they could do on their own? They do seem to have pretty impressive bass for a bookshelf! I just picked up a pair of DCM bookshelf speakers off e-bay for my workout room...they don't play anywhere near that low but do quite well for the $80 I spent for them brand new! Surprised me....I think they play lower than the Hsu speakers I sold.

I'm leaning towards the Nord 3 channel NC500 but for the same price, I can get a 7 channel Monolith....less power for sure but still more than my current speakers are rated for. One big issue for me is I honestly don't know how I can put a 95 lb amp in my room :oops:
 
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I always thought NAD underrated their power specs. Is that still the general feeling based on measurements? They claim X on paper, but deliver more in the real world?
 
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I always thought NAD underrated their power specs. Is that still the general feeling based on measurements? They claim X on paper, but deliver more in the real world?
Just taking the review and NAD's ratings into account, the review seems to show issues with their ratings.

According to NAD this receiver will do 110W into 8 ohm speakers, however Amir barely got 80 watts out in this configuration. He does mention that it is a healthy amount of power (and it is for any reasonably sensitive, modern speaker), but ratings are ratings. I don't even know how NAD rates a S/N ratio of >100dB given Amir's holistic findings, though I think that's more because SNR != SINAD.

It's interesting because although it is a healthy power amplifier circuit for a receiver compared to others in the class (Pioneers in particular were shutting down during tests) it is still not able to meet the spec. I don't think any manufacturer under rates their products consistently but I'd be interested if anyone knows of some that do.
 
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After awhile owning this receiver, I keep noticing a bug with the audio processing and I wonder if it is related/causes the poor DAC measurements from OP. Not that it would bode well for NAD since requiring a bug to pop-up for things to work right is bad any way you slice it. But I digress. I've brought this up before and I think there's value in discussing since I realized it effects output levels on the pre-outs. I will likely file a report with NAD eventually, but I am truly still trying to become familiar with what causes this.

I first noticed this bug when doing my usual setup and checking responses/tweaking my sub's miniDSP. So laptop to receiver via HDMI. When I would send a test signal to the LFE channel, the receiver would seemingly find another 15-20dB of headroom (with no user changes to the signal path), usually causing clipping and making me confused. Prior to sending this LFE channel signal, sending a signal to any other speaker would seem normal. Levels wouldn't suddenly increase unless that signal was sent to LFE. And after that, all speakers would have this boosted volume characteristic.

Okay, maybe that was just that setup while tweaking things. But then I noticed the bug again on an analog source after my receiver auto-slept. After waking it and flipping to the next side, volume was WAY higher than the previous side. I thought "maybe it's just this record," but eventually realized it was the same bug. Didn't think much beyond that.

The last time I noticed this bug is on a PS4 (another different source). I had probably been playing an hour or two when some sound event caused the volume to quickly ramp up. I assume something came across the LFE channel like I saw when tweaking things in the first example, but I knew immediately it was the same bug and things finally clicked for me.

So, the million dollar question: what if Amir's testing never tripped this bug and the DAC's true performance is hidden behind an implementation error? Anecdotally I think it would have a severe impact on SINAD. At least, I highly doubt that SINAD would be identical for the two scenarios.

Sort of sucks to ask this now since the receiver he tested is long gone, but I'm almost interested enough to float the cost and send another one to help prove it.
 
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I've arrived here after strongly considering this avr & am now facing dilemma.

Would running an external dac bypass the receivers inferior on-board dac or is the sound still going to get mucked up either way? Is the power amp section decent or poor? I don't quite understand some of the stuff I've read here, sorry.

Are there any suggestions for a comparable avr but with better results?
 
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