ADVICE: OPPO 203 (Preamplifier) + Emotiva A-5175 (Living Room Home Theater)

[sterling shoote]

The P6's ES9018 K2M specs are:
127dB DNR, –120dB THD+N

The Oppo 205's flagship ES9038Pro specs:
140 dB DNR, -122 dB THD

So the 205's DACs implemented in differential mode has distortions so low and DNR so high that only Superman, Supergirl and Wonderwoman can hear the difference between them and the one used in the P6.

The P6's DAC's THD+N and DNR can already challenge the limits of the Audio Precision analyzer, may be that's why it seems to give you the same details as the Oppo's lol..

The means at hand to contrast and compare OPPO and Parasound DACs is via usb output from iTunes 24/192 material; and, listening to this material, I cannot distinguish that one means to the music is better than the other. However, since the OPPO processes usb input sans .1 while the P6 does processes for .1 output, the Parasound is usually how I roll for stereo sources and the OPPO is relegated to 5.1 pleasure via SACD or usb drive.

 

[Venue]

By the way, if you have time, try the Klippel test. It may not mean anything to you, but you may find it fun to do.

Listening Test (klippel.de)

How far does the range go?
I'm at -18dB, all correct so far, shitty laptop (cheap) and so-so in-ears.

 

[Venue]

Ok, first time results, no Hi-Fi setup by any means:

https://i.postimg.cc/SsXvfJdx/Screenshot-2021-03-15-Listening-Test.png

Don't know why it skipped -27dB.
Would this test at -79dB reflect the performance of the Marantz?

 

[PENG]

Ok, first time results, no Hi-Fi setup by any means:

https://i.postimg.cc/SsXvfJdx/Screenshot-2021-03-15-Listening-Test.png

Don't know why it skipped -27dB.
Would this test at -79dB reflect the performance of the Marantz?

The distortions added were of the types from loudspeakers so would be lower orders. SS amps typically have higher orders harmonics as well so it's not exactly apples to apples. Still, I would think with THD+N at - 75-76 dB for a Marantz AVR it can't be worse than loudspeaker's at - 70 dB. I don't really know, just guessing and I can find any technical paper on this topic. I hope you can.

In my thread on distortions you can see other's scores, no one did better than - 42 dB so far.

Most people don't find it hard to hear differences between speakers. It's much more difficult to hear the differences between amps unless you know which one you are listening to.

 

[PENG]

How far does the range go?
I'm at -18dB, all correct so far, shitty laptop (cheap) and so-so in-ears.

No idea, at ASR, someone manage - 54 dB if I remember right, but he identified a hiss that gave him the clue so not really valid. I guess it would keep going lower if someone can go that low and keep passing the test.

 

[PENG]

Venue, take a look of the following side by side comparison of their harmonics contents, and that of one of the best measured loudspeaker:

Note: The one for the B&W_705S2 shows the total harmonic distortions for the narrow range of just 50-10,000 Hz, so just keep that in mind, not an apples to apples comparison, while the Marantz Vs Denon is.

I don't know what conclusions we can draw from this measurement, but it looks obvious the Denon actually has more 2nd harmonics than 3rd, whereas it is the opposite for the Marantz. According to Nelson Pass (since you seem to be a believer in subjective views, you must know who he is right?), some people actually prefer 3rd harmonics than the 2nd that are often associated with the so called "warm sound", if I remember he said something like 50/50. I 'll try to search it for you and will post a link.

You an see that even the Marantz's THD+N was 80 dB below the fundamental, and the main ones that's mostly contributed by the 3rd harmonics. By the time it hits the 5th harmonic, it was already at -110 dB, who can hear that?? I would say again, got to be Wonderwoman if not Superman.



ASR_Review_Marantz SR7015 Versus AVR-X3600H

So I would never say all amps or DAC sound the same, I know they don't, not always, and there are always exceptions. However, I dare say D+M's claims of using their human sound master to tune their sound are just marketing talks, not credible, as one of the highly respected amp designer Peter Walker supposedly said in an interview (https://geocities.restorativland.org/ResearchTriangle/Lab/6722/pwint1.txt):

"PW: We designed our valve (tube) amplifier, manufactured it, and put it on the
market, and never actually listened to it. In fact, the same applies to the 303 and
the 405. People say, "Well that's disgusting, you ought to have listened to it."
However, we do a certain amount of listening tests, but they are for specific
things. We listen to the differential distortion - does a certain thing matter?
You've got to have a listening test to sort out whether it matters. You've got to do
tests to sort out whether rumble is likely to overload pickup inputs, or whether
very high frequency stuff coming out of the pickup due to record scratch is going
to disturb the control unit. But we aren't sitting down listening to Beethoven's
Fifth and saying, "That amplifier sounds better, let's change a resistor or two. Oh
yes, that's now better still." We never sit down and listen to a music record
through an amplifier in the design stage. We listen to funny noises, funny
distortions, and see whether these things are going to matter, to get a subjective
assessment. But we don't actually listen to program material at all."

He also said:

"The peripheral effects are what get people into trouble. You can
see why you find these differences in amplifiers. You can always find them. If
people test two amplifiers and say, "These sound different," there's no magic in
it. Spend two days, maybe a whole week in the lab, and you find out exactly why
they're different and you can write the whole thing down in purely practical,
physical terms. This is why these two sound different, and the cause is usually
peripheral effects. It is not really a case of good or bad amplifiers, it's that the
termination impedances are wrong, or something of that sort."

If he's right, then again, all amps can sound different, but because of those what he called "peripheral effects"? Not the amps themselves?

Not trying to convince you one way or another, obviously you can do your own research and draw you own conclusions, or not. .

 

[PENG]

Found the magic device for Venue:

Pass H2 Harmonic Generator - Positive Feedback (positive-feedback.com)

Its almost sound strange when he said:

"Introduction – Why do we care about 2nd harmonic?
Historically, audio amplification has been about the elimination of all forms of distortion. Early on, the premise has been that low distortion is one of the keys to audio quality and this was certainly true back when amplifiers had a lot of distortion. But in the past forty years or so distortion has been reduced to very small amounts, and as a practical matter the problem is solved."

I am very interesting in building that generator, for fun only though.

and here's the one Nelson Pass wrote about 2nd vs 3rd harmonics, that is, the audible effects of..

Pass LabsAudio distortion and feedback - Pass Labs

"Many audiophiles believe that 2nd harmonic is to be preferred over 3rd harmonic. Certainly it is simpler in character, and it is well agreed that orders higher than third are more audible and less musical. However when given a choice between the sound of an amplifier whose characteristic is dominantly 2nd harmonic versus 3rd harmonic, a good percentage of listeners choose the 3rd. "

"The sound of 2nd order type circuits is often praised as “warm” and by comparison 3rd order type circuits are often noted for “dynamic contrast”. 2nd order type amplifiers seem to do particularly well with simple musical material, and 3rd order types generally seem to be better at more complex music."

If you read the whole article, you will catch all the nuance, its more complicate than I put in quotes above, and you will likely see what I see that even him, believe in well designed amps are not likely responsible for the perceived sound signatures by Audiophiles. For example, he would say "Many audiophiles believe..........", never said he himself believe, just one example.

 

[Venue]

Sorry, this is all new to me, I don't have much clue of the above.

Is the 1st harmonic at 1kHz, presumably the test signal done by ASR?
Or is the 1st harmonic the first 'peak' after the test signal, it being 1kHz in this case, i.e. 2kHz?

I'm trying to think logically, again, I don't have much clue, but I think maybe these charts are called FFT?
Looking at the charts, aren't vocals mainly within the 1000-4000Hz range?
If so, depending on where the 1st harmonic starts (1kHz or 2kHz) you would perhaps want them all as low as possible, -80dB (-79dB) as the Marantz show seem to be inferior performance, again, to which extent?

I think I would need an answer to how exactly these -dB measurements translates into real world audio performance, in volume, I mean is -80dB on these charts 80dB of volume/audio? Or, is the -80dB related to the klippel test we did just a page back? If it is, I would have no chance in hearing either, I don't think any human would, perhaps if you have a real mint Hi-Fi setup, in a well treated room, then maybe, but what do I know, I've never been there.

In the end, what drives a consumer's decision, is A/B comparisons, whatever A/B can you make perform prior to a purchase is by looking at tests like these, or by general specifications, the conclusion lands where it lands, the Denon appears superior, does it translate to a discernible difference in real life? Well, I don't think anyone of us really knows?

 

[Pogre]

I don't A/B test receivers or amps because in general the differences in distortion ratings among the competent manufacturers are well below audibility for human hearing. I look for features, dsp/bass management and the appropriate power to drive my speakers.

I put my energy into my speakers and room. I don't waste it quibbling over inaudible differences.

Pretty sure we've said this about 15 times in this thread so far... lol.

 

[Pogre]

I think you did say, but I forget. Which speakers and subs did you get? You said you haven't unboxed anything yet? If you wanna quibble over meaningful specs I can possibly show you some examples...

 

[Venue]

Klipsch RP-8000F's, RP-504C, RP-502S's, SPL-150's, not changing.

 

[PENG]

Is the 1st harmonic at 1kHz, presumably the test signal done by ASR?

The 1 kHz one is the fundamental frequency of the test signal. I suppose you can call it first harmonic, but fundamental is probably more appropriate. If there was no harmonic distortions at all, it would show a pure sine wave tone at 1 kHz, that is you will see just the fundamental on the FFT, obviously there will always be some distortions, even the Audio Precision analyzer itself will generate some, however minute it is.

I'm trying to think logically, again, I don't have much clue, but I think maybe these charts are called FFT?
Looking at the charts, aren't vocals mainly within the 1000-4000Hz range?
If so, depending on where the 1st harmonic starts (1kHz or 2kHz) you would perhaps want them all as low as possible, -80dB (-79dB) as the Marantz show seem to be inferior performance, again, to which extent?

Yes, that it what they call FFT, Fast Fourier Transform. Any waveform, even a square wave, can be represent by a Fourier series of sine waves.

Below is a link to a simple demo/explanation:
Confusions on FFT of a square-wave in theory and in scope and simulation - Electrical Engineering Stack Exchange

You do want harmonic distortions to be as low as possible for the test signal of 10 kHz and below, and yes much more so for the 1000-4000 Hz range, in fact better still, for the 400 to 5000 Hz range because humans are most sensitive to the 2000 and 5000 Hz range, and the 5th harmonic of 400 Hz is about 2,000 Hz, right there in our sensitive range.

I think I would need an answer to how exactly these -dB measurements translates into real world audio performance, in volume, I mean is -80dB on these charts 80dB of volume/audio? Or, is the -80dB related to the klippel test we did just a page back? If it is, I would have no chance in hearing either, I don't think any human would, perhaps if you have a real mint Hi-Fi setup, in a well treated room, then maybe, but what do I know, I've never been there.

Considering the following may help:

- 0 dB spl is generally consider the threshold for human, man anyway, women probably do a little better. In the 2000-5000 Hz range, those with the best hearing can hear at levels below 0 dB, that is, into the negative range.
| Cochlea
Absolute threshold of hearing - Wikipedia
- Your room not an anechoic chamber, so there will be noise, I don't know about yours, mine is above 20-30 dB.

In the real world, as you are asking, you can see that if you listen to a very loud reference level, that is 105 dB peak, harmonics at the -80 dB level would be at 105-80 = 25 dB. That means you probably can hear it under some conditions, such as when the harmonics are within the 2,000 to 5,000 Hz range, and harmonics in that frequency range would have to be the 2nd, 3rd, 5th harmonics of the signal from 400 Hz (fundamental) and up, assuming we ignore the higher order harmonics (such as the 7th, 9th, etc.). If you listen to maximum SPL of 80 dB, then at -80 dB, the harmonics would be at 80-80 = 0 dB level, not much chance for you to notice that level of harmonics.

So the answer to your question is, it depends on how loud you listen, how quiet is your listening environment, what kind of music you listen to, and how good your hearing is etc. etc..

The distortions don't need to be at 0 dB either for you to not notice it, because the music's fundamental frequencies and even the noise, will have some masking effects so you can't easily tell the difference even if the THD level by itself is above the threshold of audibility.

Or, is the -80dB related to the klippel test we did just a page back? If it is, I would have no chance in hearing either, I don't think any human would, perhaps if you have a real mint Hi-Fi setup, in a well treated room, then maybe, but what do I know, I've never been there.

Yes, same idea, and I think you are right, that if you could not pass the Klippel test at say near the -70 dB level, there is little chance you can differential a device that has THD+N of -80 dB and one that has it at -90 dB.

I wouldn't say 100% for sure because the Klippel test uses the kind of distortions produced by loudspeakers, that means the harmonic would be mostly 2nd and 3rd, whereas class AB amps, even tube amps would have higher order ones, though from the 7th and up they do usually become vanishingly low as long as the amp is not push to anywhere near their clipping point. Higher order harmonics are easily to tell, in general.

If you are interested in reading up on distortions and audibility, I have included a good bunch of links to some great articles and videos in the thread on amplifier distortion.

Amplifier distortions - what, and how much are audible | Audioholics Home Theater Forums

 

[Pogre]

Klipsch RP-8000F's, RP-504C, RP-502S's, SPL-150's, not changing.

Lol. You're funny. Well, nobody is talking about changing. In fact as far as Klipsch goes you picked one of the good ones so good on you. Shady reviewed those pretty favorably here at Audioholics. You can look at the measurements right here.

Those are the specs I put some time and energy into. Speakers are the endgame for sound quality and arguably the single most important component in your entire system. Subwoofers are right up there too, and there are plenty of specs and measurements to look at for them as well. There's also measuring your in room response to improve sq. Now there's a rabbit hole that'll eat up all that extra energy you have, lol.

A Umik mic is only about 85 bucks and even if you don't plan to eq it's still useful for helping with placement and diagnosing issues. These are the types of things you can gather info on that will actually offer tangible results. All the stuff you're looking at now has little to no real impact on your end result.

 

[Venue]

@PENG not quoting that whole post, but god damn, wow, what an answer, right on the money, I learned so much, it all made full logic, thank you very much!

Moving forward, I think I my preference ends up chosing the Emotiva MC-700 processor, it fit all my needs, and I only have 1 source, so all the issues people have had will not affect me, I somewhat love the old looking menu system, coming from computers I love simplicity, the more simpler it is, the less heavy it is on the CPU, not that it matters in this particular instance, but lets just say I've grown my patience with computers during the years.

It has this DAC, Cirrus Logic 42518, see specifications in the link below:

CS42518 | Cirrus Logic

www.cirrus.com

DAC THD+N (dB) -100

This then translates to a maximum possible SPL of 100dB before it's possible to make out any distortion?
Or maybe I also need to overcome my room noise, which might be 30dB, so really an SPL of 130dB is required?
I know there might be more to the answer, the total circuitry might need to be calculated for, but the DAC is always a great starting point to look at when it comes to possible clean SPL levels?

I mean it does not matter if you have an amplifier capable of -120dB when the DAC is a limiting factor?

The DAC is only 24bit, anything to worry about with 24bit content?
144dB according to the below, can't really tie it together, could use some help on that.

Audio bit depth - Wikipedia

en.wikipedia.org

Also, everything you guys talk about is distortion, is it safe to say that this is the only parameter that can affect audio quality coming from electronics, and all the rest affecting final SQ is from speakers, room, room treatment, digital room correction etc, etc?

In that case, I have to ask, I mean I'm not stupid, I think I know the answer, lots of PR and sales involved, but, how come review websites such as WhatHiFi etc. can review different A/V receivers and putting words on them, such as, lacks subtlety, needs more low end, great punch and dynamics, clear vocals, what have you, it's all bull?

Another question which anyone might answer, Emotiva seem to label their amplifier connections with speaker channels, i.e. FL, C, FR, etc, being an electrician that I am, it makes no sense to me those labels, I mean surely all channels must be equally treated/designed inside the chassis, the circuits must look the same, or did they actually design them differently, so that FL, FR has beefier circuits or something?

Emotiva specify different wattages depending on the number of channels driven, I guess this is similar as to any A/V receiver and/or amplifier manufacturer, does it come down to having to connect FL/FR to the correct channels on the amplifier otherwise you miss out on the increased wattage capability when only using two channels, i.e. music, no?

To me the only reasonable explanation would be that the circuitry design allows for more power the less input signals that are present, not depending on how you connected the speakers and/or pre-out/pre-in cables, correct/false?

Also (lol) when you calibrate, in this case, using the 11-band PEQ provided by the MC-700, how does one determine which SPL to settle for when performing the calibration and setting the desired/target curve? Is there a logic that says one should target the same SPL level for all speakers, targeting the least sensitivite speaker, and reducing the trim on the most sensitive speaker? That is what my logic tells me to do, at least, perhaps it's correct.

Thanks for everything, you guys have been bliss!

@Pogre Yeah, I tried to do some research prior to the purchase, I heard Klipsch were famous for their dynamic sound and lots of people kept saying they were good for cinema/movies, so that was my natural choice and first preference, I actually listened to them at a local store this summer, I tried some music, didn't find it all impressive but I heard the potential for movies (there was a big sound).

Surely everything will get better once at home, properly setup, calibrated, etc.
I got two SPL-120's at first, but couldn't take my eyes off the extra low end offered by the SPL-150, so I made an exchange with my dealer, without having unboxed them, grabbed them at a great price, haven't seen the price matched yet to this day, $1699 for the pair, but I guess it's a completely different matter if my room can stand those lower frequencies, i.e. capable of accomodating them, we'll see I guess, in any case, I'll have a greater punch and impact above 20Hz, still makes for fun I would assume.

I had the UMIK-1, sold it.
I've heard you need the CSL UMIK-1 for sub-20Hz, so I'll grab that instead.
With the MC-700 from Emotiva and their manual 11-band PEQ per channel, I will be using REW + CSL UMIK-1 for all my calibration, be it with the miniDSP for my SPL-150's, or any of my other speakers hooked up to the power amplifier.

I already had that figured, though, thank you!

 

[lovinthehd]

I'm not going to quote that whole thing but whathifi is not worth much, bullshit reviews is about right (but then I find most subjective reviews in most of the mags/blogs useless, prefer to see measurements or breakdown of utilitiy of features). If you have a room that's got a noise floor of 30dB, that's very good, you never measured your noisefloor when you had the measurement mic?

 

[Venue]

No, I never thought of it, now it makes me real interested in doing so, however no mic.
I was just throwing a number out there, it's not like my room is 30dB, probably higher, lot higher.
Did you measure yours? What's yours like?

 

[lovinthehd]

Mine depends on time of day, traffic, etc, it's fairly quiet here but some background noise. My measurements have ranged from mid 30s to low-mid 40s and depends on weighting scale, too.

 

[PENG]

@PENG not quoting that whole post, but god damn, wow, what an answer, right on the money, I learned so much, it all made full logic, thank you very much!

Moving forward, I think I my preference ends up chosing the Emotiva MC-700 processor, it fit all my needs, and I only have 1 source, so all the issues people have had will not affect me, I somewhat love the old looking menu system, coming from computers I love simplicity, the more simpler it is, the less heavy it is on the CPU, not that it matters in this particular instance, but lets just say I've grown my patience with computers during the years.

It has this DAC, Cirrus Logic 42518, see specifications in the link below:

CS42518 | Cirrus Logic

www.cirrus.com

DAC THD+N (dB) -100

This then translates to a maximum possible SPL of 100dB before it's possible to make out any distortion?
Or maybe I also need to overcome my room noise, which might be 30dB, so really an SPL of 130dB is required?
I know there might be more to the answer, the total circuitry might need to be calculated for, but the DAC is always a great starting point to look at when it comes to possible clean SPL levels?

I mean it does not matter if you have an amplifier capable of -120dB when the DAC is a limiting factor?

The DAC is only 24bit, anything to worry about with 24bit content?
144dB according to the below, can't really tie it together, could use some help on that.

Audio bit depth - Wikipedia

en.wikipedia.org

Also, everything you guys talk about is distortion, is it safe to say that this is the only parameter that can affect audio quality coming from electronics, and all the rest affecting final SQ is from speakers, room, room treatment, digital room correction etc, etc?

In that case, I have to ask, I mean I'm not stupid, I think I know the answer, lots of PR and sales involved, but, how come review websites such as WhatHiFi etc. can review different A/V receivers and putting words on them, such as, lacks subtlety, needs more low end, great punch and dynamics, clear vocals, what have you, it's all bull?

Another question which anyone might answer, Emotiva seem to label their amplifier connections with speaker channels, i.e. FL, C, FR, etc, being an electrician that I am, it makes no sense to me those labels, I mean surely all channels must be equally treated/designed inside the chassis, the circuits must look the same, or did they actually design them differently, so that FL, FR has beefier circuits or something?

Emotiva specify different wattages depending on the number of channels driven, I guess this is similar as to any A/V receiver and/or amplifier manufacturer, does it come down to having to connect FL/FR to the correct channels on the amplifier otherwise you miss out on the increased wattage capability when only using two channels, i.e. music, no?

To me the only reasonable explanation would be that the circuitry design allows for more power the less input signals that are present, not depending on how you connected the speakers and/or pre-out/pre-in cables, correct/false?

Also (lol) when you calibrate, in this case, using the 11-band PEQ provided by the MC-700, how does one determine which SPL to settle for when performing the calibration and setting the desired/target curve? Is there a logic that says one should target the same SPL level for all speakers, targeting the least sensitivite speaker, and reducing the trim on the most sensitive speaker? That is what my logic tells me to do, at least, perhaps it's correct.

Thanks for everything, you guys have been bliss!

@Pogre Yeah, I tried to do some research prior to the purchase, I heard Klipsch were famous for their dynamic sound and lots of people kept saying they were good for cinema/movies, so that was my natural choice and first preference, I actually listened to them at a local store this summer, I tried some music, didn't find it all impressive but I heard the potential for movies (there was a big sound).

Surely everything will get better once at home, properly setup, calibrated, etc.
I got two SPL-120's at first, but couldn't take my eyes off the extra low end offered by the SPL-150, so I made an exchange with my dealer, without having unboxed them, grabbed them at a great price, haven't seen the price matched yet to this day, $1699 for the pair, but I guess it's a completely different matter if my room can stand those lower frequencies, i.e. capable of accomodating them, we'll see I guess, in any case, I'll have a greater punch and impact above 20Hz, still makes for fun I would assume.

I had the UMIK-1, sold it.
I've heard you need the CSL UMIK-1 for sub-20Hz, so I'll grab that instead.
With the MC-700 from Emotiva and their manual 11-band PEQ per channel, I will be using REW + CSL UMIK-1 for all my calibration, be it with the miniDSP for my SPL-150's, or any of my other speakers hooked up to the power amplifier.

I already had that figured, though, thank you!

For you, I would try to answer every questions if I know the answers, but as you know in my amp distortion thread I included many links, and highlighted the highly recommended ones (by me) so I would ask you to read the following first and then narrow down your remaining questions. I have the feeling you will find some of your questions answered in the linked articles.

Interpreting THD Measurements - Think dB not Percent! - Benchmark Media Systems

If you have the patience, please also read the following, that I forgot to include in my thread:

Dynamic Range: How Quiet is Quiet? | Audio Science Review (ASR) Forum

In the Benchmark one, it explains why we should think dB, instead of %, your questions about audibility just proved they are so right.

Just want to saying something as an aside:

It may be worth noting that it is a shame many audiophiles don't understand all those weird looking so called real music waveforms are in fact a bunch of pure sine waves combined together!! Remember the talks/myths about how you can go by measurements because amps we don't listen to sine wave, and amps have to deal with multiple music wave (all the ugly waveforms) at different frequencies simultaneously blablabla..!!

In fact, even a 1,000 Hz square wave can be represented by an infinite series of a 1,000 Hz pure sine wave and its odd harmonics. If you draw it out to the nth odd harmonics, i.e. 3rd, 5th,.......nth harmonics where n it infinity, you will get a perfectly square wave. Same for the violin's waveform, and an amp doesn't know or care the waveform, they just amplify the voltage at an instant, amplify it linearly, that's it, shapes of the whole wave in one cycle makes no difference to them, not even if it is square if slew rate is high enough. It obviously cannot reproduce a square wave at the output, but that's just about the only exception, other than that a well design amp should have no issue amplifying any input music signals.

Violint:

If you feed the above violin's undistorted waveform to an amp with 0% distortion, then the amp will output the signal the amplification factor without "distorting" the waveform. That is, for a linear amplifier, Vout=A X Vin, A is a constant, the amplification factor. That would be Peter Walker's ideal amp, a straight wire with gain.

The FFT simply transform the "ugly" non sinuisodal wave into a sine wave at the fundamental frequency (the frequency of that ugly wave) and the associated sine waves at the harmonic frequencies that, combined together, result in the original ugliness instead of a smooth looking sine wave.

About FFT, I think the whole communication tech thing has to thank Mr. Fourier, without him and a few other engineers/scientists, we wouldn't have our beloved cellular phones for sure.., and no audioholics either, that's just my belief.

 

[PENG]

@PENG not quoting that whole post, but god damn, wow, what an answer, right on the money, I learned so much, it all made full logic, thank you very much!

The pleasure it all mine! It is really good to have someone like you who would come and ask a lot of questions, and even obviously have some preconceived ideas, yet are open minded to consider the inputs/feedback from others.

 

[PENG]

Also, everything you guys talk about is distortion, is it safe to say that this is the only parameter that can affect audio quality coming from electronics, and all the rest affecting final SQ is from speakers, room, room treatment, digital room correction etc, etc?

No it is not the only one. Take a look of the linked post, the guy did a good job spelling out quite a few:
Audibility thresholds of amp and DAC measurements | Audio Science Review (ASR) Forum

His recap at the end:

Recap of thresholds

Lenient
Dynamic range, linearity: 96 dB
THD, IMD: -66 dBFS / 0.05%
Noise: -85 dBFS / 0.005%
SINAD: 85 dB
Crosstalk: -60 dBFS
Jitter: -110 dBFS, -100 dBFS around the main tone
Frequency response: ±0.5 dB
Channel balance: 1 dB
Output impedance: 2 ohms

Strict
Dynamic range, linearity, SINAD: 120 dB
THD, IMD, noise, crosstalk, jitter: -120 dBFS / 0.0001%
Frequency response, channel balance: ±0.1 dB
Output impedance: 0.16 ohms

Take those as just rough guidelines.

In that case, I have to ask, I mean I'm not stupid, I think I know the answer, lots of PR and sales involved, but, how come review websites such as WhatHiFi etc. can review different A/V receivers and putting words on them, such as, lacks subtlety, needs more low end, great punch and dynamics, clear vocals, what have you, it's all bull?

I wouldn't say "all", some might be true and could also be for the peripheral reasons Peter Walker talked about, but I would say a good parts of it are.....