Measurements not Revealing Significant Differences Between AVRs and AVPs

[m. zillch]

Translation please. That makes not a lick of sense to me.

Fair enough. Here goes.

Can we sense room temperature changes of 10 degrees F? Yes.
Can we sense room temperature changes of 5 degrees F? Not as easily, but yes.
Can we sense room temperature changes of 2 degrees F? Perhaps under ideal conditions, yes.
Can we sense room temperature changes of 1 degree F? Maybe some people who are very sensitive. Not me though.
Can we sense room temperature changes of .1 degrees F? No. [This is the resolution of many even cheap ones.]
Is there any value to a human being if their room thermometer registers .01 degree changes? No, but you can still market it to people in order to sell them such thermometers.

I don't buy that previous surround processors were bottle necked in a meaningful way by their processor speed/memory just like I don't buy that room thermometers with .01 degree resolution have a meaningful benefit to human comfort.

 

[TLS Guy]

Fair enough. Here goes.

Can we sense room temperature changes of 10 degrees F? Yes.
Can we sense room temperature changes of 5 degrees F? Not as easily, but yes.
Can we sense room temperature changes of 2 degrees F? Perhaps under ideal conditions, yes.
Can we sense room temperature changes of 1 degree F? Maybe some people who are very sensitive. Not me though.
Can we sense room temperature changes of .1 degrees F? No. [This is the resolution of many even cheap ones.]
Is there any value to a human being if their room thermometer registers .01 degree changes? No, but you can still market it to people in order to sell them such thermometers.

I don't buy that previous surround processors were bottle necked in a meaningful way by their processor speed/memory just like I don't buy that room thermometers with .01 degree resolution have a meaningful benefit to human comfort.

I think you are missing the point. The improvement can not be in the FR domain. It is is in the spatial arena, especially in Atmos program.

Those previous processors were bottlenecked and seriously.

 

[m. zillch]

So we obviously disagree [and I never wrote what domain I was speaking too] but out of my own curiosity are you of the mind that finally we are hearing Atmos in all its glory (decoding wise) just as we would in a commercial cinema using the same number and configuration of speakers? And up till now we had to live with a compromised version from lesser units? Or perhaps do you believe that your AV10 now exceeds what commercial cinemas offer, in regards to electronic processing at least? Just curious.

 

[dlaloum]

I think that is a big part of it. I think the other part is the improved SNR. The SNR of my previous AVPs has not been good enough. The AV 10 is 11db. better and that is a lot.

As I listen more, I note the quiet passages are much more detailed and realistic. The problem is that with 11 channels you need a really good SNR for it not to intrude. With this new rig the background is not different whether the equipment is on or off. You can not hear any generated noise at all at the seated positions.

I have listened to quite a few Atmos streams now that I previously thought were poor and now rate excellent. The most noticeable improvement has been in the Atmos sources by far. Previously I rated Atmos as interesting but not really worth the trouble. Now I am keen on it.

One issue still remains... working out whether the subjective improvement is due to improved S/N, or due to improved decoder & mixer software ... ie: is it due to software or hardware?!

If software - then many can look forward to similar improvements all the way up and down the range for every AVR/AVP that supports the same core processor platform.

If hardware (the signal to noise) - then the improvement will be limited to the flagship models where that improvement is achieved, and will not be available to buyers of the more economical members of the current generation.

There have been no in depth reviews so far that have reported similar subjective improvements over previous generation AVR/AVP's at the mass-market levels (X3800/Cinema 50 level and up).

If the improvements are software based, then the mass market tier may be pending a firmware update that will provide the latest Dolby decoder version to gain the improvements...

The absence of information on the versions of decoder software embedded makes it well nigh impossible for us to identify this....

Does anyone in our community know of a mechanism via which we can identify the versions of the decoder versions in a processor? (both Dolby and DTS... and perhaps Auro too for those that support it)

 

[m. zillch]

I think the other part is the improved SNR. The SNR of my previous AVPs has not been good enough. The AV 10 is 11db. better and that is a lot.

Assuming you are referring to measurements by Amir/Gene I'm pretty sure that spec is for stereo sound channel reproduction with zero DSP functions engaged. It doesn't really speak to what is the SNR of Dolby Atmos processed channels nor what happens when DSP circuitry like room correction EQ processing is engaged. At least that's what they usually measure for us, as I understand it.

 

[TLS Guy]

Assuming you are referring to measurements my Amir I'm pretty sure that spec is for stereo sound reproduction with zero DSP functions engaged. It doesn't really speak to what is the SNR of Dolby Atmos channels is nor what happens when DSP circuitry like room correction EQ is engaged. At least that's what he usually measures for us, as I understand it.

I think that is correct, but spatial issues are hard to quantify. I do not use room correction as I don't need it.
The SNR does show dramatically improved results, by 11db, and this can actually make the sound seem a lot cleaner.

 

[lovinthehd]

SNR does show dramatically improved results this can actually make the sound seem a lot cleaner.

Cleaner than what? What is the definition of "clean" to begin with? Is it the distortion or base noise component that is most at issue? Any particular backup to the general claim of "seem a lot cleaner" at these levels of inaudibility?

 

[TLS Guy]

Cleaner than what? What is the definition of "clean" to begin with? Is it the distortion or base noise component that is most at issue? Any particular backup to the general claim of "seem a lot cleaner" at these levels of inaudibility?

It is easily audible. The whole multichannel presentations are changed and not by a little. The improved SNR is easily audible. 11db improvement in SNR is huge.

 

[lovinthehd]

It is easily audible. The whole multichannel presentations are changed and not by a little. The improved SNR is easily audible. 11db improvement in SNR is huge.

Yeah, that just more sounds like an exaggeration at best.

 

[TLS Guy]

Yeah, that just more sounds like an exaggeration at best.

11 db between the 7706 and AV 10 is from the specifications and bench tests.

 

[m. zillch]

Even a measly 1-2 dB change in a noise level is audible (but only just barely) if one pegs their volume to max and walks over to their speakers to hold their ear up to the tweeters, in a dead quiet room, and listens to a silent track, toggling back and forth between the two.

 

[lovinthehd]

11 db between the 7706 and AV 10 is from the specifications and bench tests.

At your listening levels you can hear such? Altho as Peng mentioned, only a 2ch spec tested by 3rd parties.....but based on similar 2ch spec audibility, not particularly significant

 

[TLS Guy]

At your listening levels you can hear such? Altho as Peng mentioned, only a 2ch spec tested by 3rd parties.....but based on similar 2ch spec audibility, not particularly significant

The music I listen to has a huge dynamic range and yes, the noise floor of the 7705 and 7706 was easily audible at the listening position and the noise floor of the AV 10 is not. It does not take much noise to affect the quality of low level pianissimo sounds, even if you can't identify it through the signal. You can't hear a sound from all my 18 Quad amp channels even in a totally silent room, and that is the standard for quality equipment. So, now I have an AVP than is a proper match for my Quad power amps. There is no doubt about it, that the AV 10 is the first multi channel AVP I have had that is of commensurate quality to the rest of my system.

 

[m. zillch]

Even a measly 1-2 dB change in a noise level is audible (but only just barely) if one pegs their volume to max and walks over to their speakers to hold their ear up to the tweeters, in a dead quiet room, and listens to a silent track, toggling back and forth between the two.

Here's a simulation I just created so people can test themselves and there's no need to walk over to your tweeters to boost the level acoustically because I've already done that for you electrically:

https://www.dropbox.com/scl/fo/e9n3drvghr8ckeobo0n6o/AIgpXgOzEtoLS7doRn4xo_k?rlkey=tsrpkrhv7uga1k3lz1m6ezv2g&st=4y8li107&dl=1

 

[m. zillch]

The music I listen to has a huge dynamic range and yes, the noise floor of the 7705 and 7706 was easily audible at the listening position and the noise floor of the AV 10 is not.

?

The 7706 is silent at the MLP,

 

[PENG]

I think that is a big part of it. I think the other part is the improved SNR. The SNR of my previous AVPs has not been good enough. The AV 10 is 11db. better and that is a lot.

The AV7705 was measured on ASR, in facts twice, with the same not very good results versus the Denon AVR-X3700H listed at half the price at the time:

Compared to a Denon AVR that has the same preamp/dac section, but without the extra so called discrete HDAM opamp buffer, the AV7705 and AV7706 certainly have much higher distortions and noise:


Facts are facts, even packed with 9 channels of power amps and larger power supply, the AVR outperformed the AV Preamp processor, in fact they even outperformed the much more expensive AV8805 that uses extensive extra shielding, including a bunch copper plates lol..

As I listen more, I note the quiet passages are much more detailed and realistic. The problem is that with 11 channels you need a really good SNR for it not to intrude. With this new rig the background is not different whether the equipment is on or off. You can not hear any generated noise at all at the seated positions.

Yes, Marantz has been doing very well in the noise department, since the SR8015 and the AV10, wondered what happened before that??[/QUOTE]

 

[m. zillch]

Amir is wrong or at least short-sighted to stress SINAD so much, but people just gobble up the concept of battling products based on numbers. Example: "I bet my camera has more megapixels than yours!" Marketers just love this flaw in humans and they often exploit it.

SINAD is two completely different issues smashed together as one metric for no valid perceptual reason other than
both are examples of undesirable things if they exceed our threshold level of audibility,
namely noise and distortion.

I'm not a big car guy but it would be like ranking cars based on their CSAZSA, pronounced sah-zah. What's that? You've never heard of CSAZSA? Well it combines into one metric the two things which are the most important when considering the purchase of a car: Cargo Space And Zero to Sixty Acceleration.

 

[PENG]

Amir is wrong or at least short-sighted to stress SINAD, but people just gobble up the concept of battling products based on numbers. Example: "I bet my camera has more megapixels than yours!" Marketers just love this flaw in humans and they often exploit it.

SINAD is two completely different issues smashed together as one metric for no valid perceptual reason other than
"both are examples of undesirable things if they exceed our threshold level of audibility",
namely noise and distortion.

I'm not a big car guy but it would be like ranking cars based on their CSAZSA, pronounced sah-zah. What's that? You've never heard of CSAZSA? Well it combines into one metric the two things which are the most important when considering the purchase of a car: Cargo Space And Zero to Sixty Acceleration.

No he did not stress SINAD as such, in the sense that he did not do so more than manufacturers and other well known reviewers.

I of course have to agreed with you that “smashed”, together 2 metrics isn’t a good thing, but that has been what others have been doing, unfortunately, so I guess he probably just go with the flow. Like the power output in watt, that’s also a “mashed together” metric used to spec/rate/rank power amps, not ideal but..,

As to ranking, SINAD is just picked for convenience and is indeed a good way to compare, because it is a metric that other reviewers/manufacturers would at least use the same standard/protocol, such as 1 kHz sinus, the notable variance is most be not everyone use the same output level and/or input level.

He never recommended a product based only on that one metric, though I do think some of readers who do not have a strong background in audio gear and may not understand the rhmight have done so on their own as they could have been misled by the way he presented the results. You obviously are not one of those simply because of your knowledge in this field.

 

[m. zillch]

"Best" amplifiers, as per Amir/ASR. this ranking chart, based on SINAD, is taken from his Topping LA90 Discrete review (hence why that one happens to be highlighted in red)

source: https://www.audiosciencereview.com/forum/index.php?threads/topping-la90-discrete-amplifier-review.43756/

What's the most important thing we need to know about audio electronics, even before its price, ASR? Hmm. . .

source: click on "Audio Electronics" in the top section, here:

Master Audio Review Index

www.audiosciencereview.com

 

[PENG]

"Best" Amplifiers, as per Amir

source: https://www.audiosciencereview.com/forum/index.php?threads/topping-la90-discrete-amplifier-review.43756/

May I ask what's you issue with that "Best", when that amp best may other amps he tested, such as the following:

Clearly the guy based his remarks on many metrics, not just SINAD!! I hate to have to copy/paste so much here, but you forced me to do it lol... Now, let's give the guy a break, and even some credits, note that Gene measured THD+N (smashed two together) too, it has been rare to see THD and noise measurements individually in recent years. Pretty much all DAC, preamp, power amp specifications also list THD+N, not THD by itself.

Again, we are in agreement, but I don't think is is fair to pin point this on Amir, it gives people the wrong impression to single him out on this "issue".

It is a bit like my dislike of the use of watt as a metric to rank/rate/specify power amp output, as it is also smashed two important metrics, i.e. current and voltage together, but unfortunately that's the way it is, wish it could change eventually far into the future but I am not optimistic on that one either.

The fact is too, that it is much easier and quicker to measure those smashed together metrics, that individually, even with the likes of the expensive and advanced instrument such as Audio Precision's.

Reactive Load Testing
The LA90 has a very sharp clipping point. This means that it goes from vanishingly low distortion to full clipping. Combine this with aggressive protection circuit which shuts the unit off and you have the make up of a system that can't be measured in batch mode as my Powercube setup uses. If I set the voltage for 8 ohm load, then it causes the amp to shut down when driven at 4 ohm. Good news is that the amplifier doesn't care about reactive loads. Here are the results for 8 ohm for example:
Code:
Maximum Output
4/11/2023
12:13 AM
Maximum Output Level Results
Selected Load Ch1 (Vrms) Ch2 (Vrms)
8 Ohm; 60 deg Capacitive 21.2 21.3
8 Ohm; 30 deg Capacitive 21.1 21.2
8 Ohm; 0 deg Resistive 21.0 21.0
8 Ohm; 30 deg Inductive 20.2 20.3
8 Ohm; 60 deg Inductive 20.9 21.0