Marantz AV 10 installed: - Early Review and Impressions.

[Trell]

SINAD is a useful generalized number. It's not an end-all-be-all. It's a number that says - if you are playing a recording at an SPL that equals the SINAD number, all the 'measured' distortions in the SINAD number are at or below audibility. Inference example - SPL is 110 dB spl; SINAD of component is 110; Audible distortion of component is 0dB spl or less. 0dB spl is a reference for audibility - It's not silence.

The greater the SINAD number, the less chance there will be audible distortion. Distortion in this case is comprised of elements of the sound that are measured.

Baked into the definition SINAD (SIgnal-to-Noise And Distortion, typically measured at 1 kHz) is noise, and that means that for the same SINAD number there can be different amounts of noise and distortion. While humans listen to a fair amount of distortion without noticing it, the noise can be much more easily apparent.

There are other measures that gives a better information but then we're typically looking at graphs. If you go to ASR you'll see many reviews making such measurements.

Amps and preamps do sound different. My own references for SOTA sound quality and neutrality are the Benchmark products. I don't claim they are the only references. I claim they are in the rare camp of real references. There is more than enough online data to explore these thoughts. Many pros use their products for references. They are very reliable. They are very hi-end for home use without being ridiculous in price.

My pro references were - Neve, SSL, Euphonics, JBL, Genelec, QSC, dbx, Grass Valley, Shure, Crown, EV, and host of other variable quality equipment. I didn't use any stand alone preamps.

I don't particularly care for amps/DSP/electronics to be built-in the speakers. Having the electronics in a component subject to large mechanical and acoustical vibrations is counter productive. Snarky opinion - it's the definition of insanity, at least in home situations where the maximum in sound quality and longevity is desired. It has better application in some pro venues.

Genelec, one of your stated preferences, have been making active monitors for decades. They work excellently for home use as well, and in my case desktop. I've two Genelec 2.1 setups that works fine, have so for years, and I expect to get many more years of usage out of them.

 

[AcuDefTechGuy]

It's generally a bad idea to put audio electronics in or next to devices that vibrate.

Thank you! That's what I've been saying for years.

 

[TLS Guy]

One can check system information to see just what the hell is going on. One can also post a pic of that information for the benefit of all.
View attachment 73769

So, I have got round to doing what you wanted. It does not let you show an eARC input. When you try you can't see the setup screen. Anyhow I used a BPO BD disc that sounds identical to the stream of the same program.

So this is the photograph of the input screen you asked for. I doubt that will make you much the wiser, as I already told that information.

Now let's go back to square one. I am not going to the trouble of doing measurements on this unit on the bench. First it has been measured by two competent individuals so I would have nothing to add. The measurements are exemplary, with SNR having a colossal improvement.

I did not buy the AV 10 with the expectation of greatly improved SQ, except for absence of audible background in a silent room. This I have verified and the room no signal is totally quiet. You would not know the rig was on, with the other AVRs you did, as soon as they were switched on. Part of this is due to that fact 12 drivers in the system are directly connected to their amps with no passive crossover. A passive crossover will attenuate the signal 3 to 12 db depending on order, so 3db of first and 6db for second and so on.

Now lets address why I made the mistake of buying the 7706. I guess I figured that the AV 10 would not be a huge improvement, it was costly and I thought the 7705 failure was bad luck. But I think the bigger reason was idleness. The 7706 was physically and exact replacement.

The AV 10 is taller, longer and weighs 37lb. It also required a costly (over $300.00) and heavy aftermarket rack case. In this rig it has to be rack mounted, no doubt about that. So getting the weight up to 50 lb. meant careful thought. That is far too much weight to be supported just on the front rack ears. Truly pro equipment of that weight goes between the front AND back mounting holes, so is bolted to the rack front and back.

So I had to contrive a shelf on rails between the front and back girders of the rack. This worked well. Then there were gaps, as the mount had standard spacing but other domestic units do not. So I had to fashion spacers to supplement the two 3U rack spacers I bought. These had to be fabricated in my shop and painted. This whole process spread over three days, actually four with all the set up and measuring.

Now whether you want to believe me or not, the sonic soundstage presented by the AV 10 is dramatically better and more realistic than the two that went before. The BPO call their Atmos stream immersive audio. With the 7705 and 7706 the sound was in no way immersive, with the AV 10 it truly is. This is the first time I have truly heard the famed acoustic of the Philharmonie in Berlin. You realistically hear the ring of the hall and superb left right, front back and height representation of the orchestra choirs and high balcony musicians and choirs when present. The previous units fell way short of that realization. I am not imagining that, it is the absolute truth, whether you want to believe it or not.

So, this leads me to speculate on the practicality of the point we have reached in home audio.

I think a good reason that the other units failed was that they were based on AVRs, and the components did not have adequate spacing. When I build my HTPCs and DAWs, I am very fussy as to layout. I measure temperatures of critical components carefully, and my builds have had very "long legs". This was one of many lessons I learned from Peter Walker, that internal layout is critically important. If you throw it together it will be short lived.

That gets me to the point I been hammering for a long time, especially as complexity has increased and the number of power amps increased at the same time.

So, in my view an Atmos receiver is a total waste of time and resources. More than two or three power amps to a case runs it a close second.
This is especially true with Atmos, as the speakers other then the front three can take significant power.

I honestly think if we are going to pursue all these channels and speakers, it makes the case for active speakers. This not only makes more room in the AVP for better cooling and longer life, but effectively frees up space in the room. The big advantage is that it means there will only be two or three amplifiers per box. The will end this power per channels driven nonsense. Power amps should be able to deliver their designed power at anytime called for, and NOT dependent on what neighboring amps are doing. That is the route to disaster.

So yes, I am pleased I now have the AV10 installed with results above my expectation, but it highlights that in terms of home AV system we are driving headlong down the wrong road to the cliff. We need to change our hardware architecture and current practices fast, or people will get more discouraged than they are now.

 

[lovinthehd]

Mixed in Atmos, not upmixed.

I see this for the Berlin Philharmoniker stream:
"In the Philharmonie Berlin, the unique sound of the Berliner Philharmoniker meets an important component of the musical experience: space. It is precisely this spatial experience that we want you to feel directly.We achieve this by recreating the spatiality of the auditorium with a complex algorithm when mixing the sound signal. And since every musical work has a different line-up and the instrumental groups are not always seated in the same place on stage, we create each mix with individual parameters for each individual work.An important role is played here by an upmix process specially adapted to the Philharmonie Berlin, which was developed by sound engineer Benedikt Schröder and, in collaboration with Andreas Wolf, is used to mix the concerts in the Digital Concert Hall. This then converts the concert recordings in stereo into Dolby Atmos 7.1.4.The new Immersive Audio format is available at no extra cost.

 

[Trebdp83]

There is no need to continue to apologize for purchasing the 7706. It was a practical replacement for the 7705. Now, you have the AV 10 and all is well. Two failed units out of many sold is no cause for alarm. Though, it is a bummer if you owned both of them.

Everybody budgets a certain amount of money for their personal interests. Some spend fortunes on music festivals, which have gotten criminally expensive, and some on physical music media and equipment. The finest components and state of the art processing do not come cheap. That is simply the way it is. Unfortunately, Smart speakers and soundbars have been marketed as being every bit as capable as better components and speakers. They are more convenient for many for sure, but they aren't exactly giving those pieces of s#%t away these days.

Quality powered monitors are also extremely expensive and if one wants a 9.4.6 configuration, they'd better have lots of power outlets and cash on hand. A middle of the road set of speakers and AVR make sense for many and, if set up properly and played within their limits, can deliver many years of movie and music enjoyment.

 

[TLS Guy]

I see this for the Berlin Philharmoniker stream:
"In the Philharmonie Berlin, the unique sound of the Berliner Philharmoniker meets an important component of the musical experience: space. It is precisely this spatial experience that we want you to feel directly.We achieve this by recreating the spatiality of the auditorium with a complex algorithm when mixing the sound signal. And since every musical work has a different line-up and the instrumental groups are not always seated in the same place on stage, we create each mix with individual parameters for each individual work.An important role is played here by an upmix process specially adapted to the Philharmonie Berlin, which was developed by sound engineer Benedikt Schröder and, in collaboration with Andreas Wolf, is used to mix the concerts in the Digital Concert Hall. This then converts the concert recordings in stereo into Dolby Atmos 7.1.4.The new Immersive Audio format is available at no extra cost.

Some ad man with no clue wrote that. In some of the views you can see they have the classic University of Sheffield classic Atmos mic setup, and in any event that have an advanced digital studio I have seen pictures of. Of course they are going to keep digital files from each recording microphone, everyone does that now. The Atmos mix is released about 3 to 4 months after the 2 channel release, and you can tell they have put a lot of work into it.

 

[TLS Guy]

There is no need to continue to apologize for purchasing the 7706. It was a practical replacement for the 7705. Now, you have the AV 10 and all is well. Two failed units out of many sold is no cause for alarm. Though, it is a bummer if you owned both of them.

Everybody budgets a certain amount of money for their personal interests. Some spend fortunes on music festivals, which have gotten criminally expensive, and some on physical music media and equipment. The finest components and state of the art processing do not come cheap. That is simply the way it is. Unfortunately, Smart speakers and soundbars have been marketed as being every bit as capable as better components and speakers. They are more convenient for many for sure, but they aren't exactly giving those pieces of s#%t away these days.

Quality powered monitors are also extremely expensive and if one wants a 9.4.6 configuration, they'd better have lots of power outlets and cash on hand. A middle of the road set of speakers and AVR make sense for many and, if set up properly and played within their limits, can deliver many years of movie and music enjoyment.

I would bet there are a lot more of those 7705 and 7706 units blowing up than we know about. If that is not so, then the odds of me ending up with two duds would be enormous.

 

[Trebdp83]

You are just lucky I guess and beat the odds.

 

[PENG]

I'm just skeptical somewhat with a subjective impression generally.

Surely we are not the only one, and I would think that Dr. Olive and Dr. Toole, among other widely respected as experts on audio hifi, psychoacoustic etc. are in our camp on this too.

I'm just somewhat doubting the change in dac/processing would produce such night and day type results....

Not so much dac perhaps, but processing would/could produce easily audible differences on all else being equal basis, though day and night would seem to be just an expression people like to use to make their points, by exaggerating, especially when they are really excited about something they did not expect but suddenly realize is happening.

 

[TLS Guy]

Surely we are not the only one, and I would think that Dr. Olive and Dr. Toole, among other widely respected as experts on audio hifi, psychoacoustic etc. are in our camp on this too.



Not so much dac perhaps, but processing would/could produce easily audible differences on all else being equal basis, though day and night would seem to be just an expression people like to use to make their points, by exaggerating, especially when they are really excited about something they did not expect but suddenly realize is happening.

What has really changed is the Atmos presentation. Previously it was underwhelming compared to now. You feel the acoustic space in way that was only hinted at before. As I have said it works like it "says on the tin". Before it did not. The other issue is SNR. No signal, the room is totally quiet before it was not. As soon as you switched on those 7705 and 7706 units you could hear background. It was not loud but audible.
So, yes that AV 10 is a significant improvement. The internal layout is much better which I hope will result in a longer life. The durability of those other units was a disgrace. It caused a huge hassle and I don't think two in a row was just bad luck. So that was the major drive to the AV 10, which you can tell has been made with extreme care and quality. As soon as you unpack it you can see the care in design and construction right away. This is on a par with my Quad amps, which always had superb internal design fit and finish. So there is no longer any junk in the core units. Essentially only the disc players are utilitarian quality. Design and construction are the cheapest route in the long term. Just look at my turntables and reel to reel tape machines. They prove that.

 

[PENG]

The subjective impression of people is used to create useful scientific data.

Of course, no one should be surprised by that fact.

Examples:

• Fletcher Munson curves The effects of that can be easily measured, the objective part that is, the subjective part will be more involved..
• The perception of the decibel change needed to double or halve the volume That is obviously subjective so yes, sure..
• That frequency response is one of the more important parameters in the perception of sound quality. Agreed, absolutely, and is one reason why it should be easy to see why so much talks about difference in SQ between amps that have excellent specs on paper and by measurements are mainly for discussions and perhaps fun for some people, if they just look at the FR measurements not only in anechoic space, but more importantly in their room.

 

[lovinthehd]

Surely we are not the only one, and I would think that Dr. Olive and Dr. Toole, among other widely respected as experts on audio hifi, psychoacoustic etc. are in our camp on this too.



Not so much dac perhaps, but processing would/could produce easily audible differences on all else being equal basis, though day and night would seem to be just an expression people like to use to make their points, by exaggerating, especially when they are really excited about something they did not expect but suddenly realize is happening.

My thought also was much more processing than the dac. This sort of subjective enthusiasm is only so useful, especially when someone attempt to reverse engineer it with their ears alone....

 

[PENG]

My thought also was much more processing than the dac. This sort of subjective enthusiasm is only so useful, especially when someone attempt to reverse engineer it with their ears alone....

I think PaulBe's point is, things like level/volume, frequency response can be assessed quite effectively (yes, always to a point) by subjective measurements. The reality is, amplification do not change frequency response significant enough for it to mean anything audible, once it gets pass the point of diminishing return such as +/- 1 dB 20-20,000 Hz with the amp operating well below clipping point. Volume/level can be matched to within 0.5 dB without too much difficulty when doing AB comparisons, yet people (I mean forum posts) who reported the different "sound" their amps produce never (almost...) seem to both such level matching and FR verification by measurements), to them subjective measurements is everything because it is their ears.

Processing is different, for obvious reasons, DTS, DD, and their variants, and upmixing etc., do sound different enough for the die hard objectivists, but it is very difficult to compare in terms of apples to apples for person HT use.

One thing I find very difficult to understand is, why don't enthusiast who believe in amps are tuned to different sound think logically, that if that is true, then amps measured on the bench will not the typical 20-20000 Hz +/- 0.5 to 1 dB, yet they do, whether we are comparing bench test results of a Benchmark AHB2, McIntosh's flagship amps, Passlab's, or a <$1000 buckeyeamp (class D), Fosi's <$100 class D chip amp.

Also, Peter Walker, the EE who designed @TLS Guy 's favorite Quad amps clearly stated they didn't tune their designs by ears, and that they only conduct listening test to make sure there's nothing unusual there in the end.

I posted the link long time ago, the link to the Geocities article no longer works though:

Interview with Quad's Peter Walker in 1978

I copied/pasted the contents at the time in the post below:

Amplifier distortions - what, and how much are audible | Page 2 | Audioholics Home Theater Forums

I highly recommend that Peter Walker interview to those who is willing to apply logic to the claim that well design amps (based on specs and measurements) do sound audibly different when the compared amps are operating at well within their input and output limits.

Again, @TLS Guy has made it clear, the much improved sound quality he referred to so far about the AV7705/6 Vs AV10 is about DSP sound, such as Atmos, he has not said anything about audibly better sound quality for non processed, such as in pure direct mode.

 

[Trell]

...
Again, @TLS Guy has made it clear, the much improved sound quality he referred to so far about the AV7705/6 Vs AV10 is about DSP sound, such as Atmos, he has not said anything about audibly better sound quality for non processed, such as in pure direct mode.

He did write this in his first post, though, which was part as to why I was snarky later on. Before the quote of him below he did write that SNR was much better, and that for sure can be audible. Distortion less so, depending, of course.

>>>Now even though the distortion is significantly lower than the previous unit, I doubt that is the reason for this improvement. I think the answer is in the improved DAC. It is well known that better DACs handle lower level signals better.<<<

 

[PENG]

He did write this in his first post, though, which was part as to why I was snarky later on. Before the quote of him below he did write that SNR was much better, and that for sure can be audible. Distortion less so, depending, of course.

>>>Now even though the distortion is significantly lower than the previous unit, I doubt that is the reason for this improvement. I think the answer is in the improved DAC. It is well known that better DACs handle lower level signals better.<<<

I hear you, that’s a diiferent topic and he is right about the much better SNR. My AV8801 has comparable SINAD to the 7705 and I could hear the noise from my mmp, 10-11 feet if I crank the vol up enough. Switched to the Denon AVR-X4400H and problem solved.

 

[Trell]

I hear you, that’s a diiferent topic and he is right about the much better SNR. My AV8801 has comparable SINAD to the 7705 and I could hear the noise from my mmp, 10-11 feet if I crank the vol up enough. Switched to the Denon AVR-X4400H and problem solved.

Sure, I've no problem at all with the part that there is less audible noise and I believe him. And in an older thread about Denon using lower SINAD DAC IC in a receiver we both, as I recall, noted that noise is an integral part (sum) of the definition of SINAD.

 

[PENG]

My main point about subjective measurement is the measurements are a set of empirical data with which to make objective conclusions. Math is developed from the subjective measurements, and then tested for repeatability. It’s science – inductive reasoning. The science stands until someone or something knocks it down. That someone is usually someone who stands on the shoulders of the someone(s) who made the previous standards.

I never thought it wasn't science, of course it is. Just that it is not a reliable way of determining, or used as proof that two amps with almost the specs in multiple metrics, and measurements including the usual suspects such as THD, DR/SNR, IMD, crosstalk, frequency response, damping factor/output impedance etc.

I wasn’t thinking of tiny differences in overall volume.

Me neither, but volume matching when comparing using something like a REW sweep 20-20,000 Hz, that's what I used in the past such as the following:

I have plenty of such comparisons, this one and all the others too, basically showed no significant differences in FR even with 1/24 smoothing (this one happens to be 1/12) and the minor differences could well be mostly due to repeatability related, considering the not super accurate U-mik-1 mic and room noises.

Concerning amplifiers –

Amplifiers are voltage amplifiers with various real world current limits. The favorite load of Any voltage amplifier in the real world, regardless of the cost and quality, is a resistor. Most speakers are a load of complex impedance – also consider this sentence an amusing euphemism. The biggest variance in frequency response of amplifiers occurs from a variability to drive a complex load. Sound quality is another matter. Most of the sound quality in an amp is derived in the ‘first watt’.

I don't disagree with what you stated, but I do feel the point of using resistor vs reactive load that most speakers are, seem not relevant if and when tests are done at well below the DUTs output limits, such as those found on ASR and Audioholics.com. For example, even an AVR such as the mid range Marantz Cinema 40 can do a very transparent job if test and measured at output up to their published rated 125 W, so if compared with any other integrated amps or separates at say the typical 5 W that ASR uses, and up to say 50 W, then who it won't matter if the load is a resistor or a simulated reactive load such as one used by the Stereophile.

Here we are looking at a mid range AVR, the matching power amps for the AV10 and AV20, the amp10 and amp20, obviously should and I suspect would measure even better when connected to reactive, even highly reactive loads.

So far, I hear the same audio improvements with all sources using the AV10. The improvements are not limited to processing, though it appears more dramatic with ATMOS discs and perhaps because of the number of channels. All my sources are disc or file. I’m not going to test why I hear improvements. I’m just going to enjoy the sound of recordings, and flawless (knock on wood) function of the processor.

I believe you and TLSGuy, and that makes me thinking of eventually selling my AVM70 and grab the AV20 or keep the AVM but also grab the presumably more affordable AV30 when it launches later this year (use either one as backup, otherwise in one of my two channel system).

* What if some of the sound and noise improvement in the AV10 is as simple as proper terminating impedances? Speculative example - The HDAM4 modules are cascodes. Cascodes linearize the signal and also have a higher output impedance. Why would Marantz engineer a higher output impedance into what is essentially a buffer?

Can's say I disagree but I do doubt that, besides according to Gene and I think some of Masimo's marketing info, the AV10/20 uses HDAM version SA3, not HDAM4.

As to their higher output impedance, its a question of what "higher" is, if it is as high as even 1 kOhm, it still wouldn't make enough difference when used with the vast majority of power amps that typically have input impedance not lower than 15 kOhm, more often in the >20 kOhm range

Besides, Marantz marketing highlighted the claimed advantages of their HDAMs are that they are discrete, that offers higher slew rate than the corresponding OPAs. That, to anyone who can think logically, should know that is probably BS, if they bother checking into the details found in service manuals, that there are other mediocre IC opas up and down stream, as well other ICs such as the volume IC, switches and of course the DAC IC, so the higher slew rate of the HDAMs, assuming it really is superior, won't make a difference, simple bottleneck analysis.

 

[TLS Guy]

I think PaulBe's point is, things like level/volume, frequency response can be assessed quite effectively (yes, always to a point) by subjective measurements. The reality is, amplification do not change frequency response significant enough for it to mean anything audible, once it gets pass the point of diminishing return such as +/- 1 dB 20-20,000 Hz with the amp operating well below clipping point. Volume/level can be matched to within 0.5 dB without too much difficulty when doing AB comparisons, yet people (I mean forum posts) who reported the different "sound" their amps produce never (almost...) seem to both such level matching and FR verification by measurements), to them subjective measurements is everything because it is their ears.

Processing is different, for obvious reasons, DTS, DD, and their variants, and upmixing etc., do sound different enough for the die hard objectivists, but it is very difficult to compare in terms of apples to apples for person HT use.

One thing I find very difficult to understand is, why don't enthusiast who believe in amps are tuned to different sound think logically, that if that is true, then amps measured on the bench will not the typical 20-20000 Hz +/- 0.5 to 1 dB, yet they do, whether we are comparing bench test results of a Benchmark AHB2, McIntosh's flagship amps, Passlab's, or a <$1000 buckeyeamp (class D), Fosi's <$100 class D chip amp.

Also, Peter Walker, the EE who designed @TLS Guy 's favorite Quad amps clearly stated they didn't tune their designs by ears, and that they only conduct listening test to make sure there's nothing unusual there in the end.

I posted the link long time ago, the link to the Geocities article no longer works though:

Interview with Quad's Peter Walker in 1978

I did copied/pasted the contents at the time in the post below:

Amplifier distortions - what, and how much are audible | Page 2 | Audioholics Home Theater Forums

I highly recommend that Peter Walker interview to those who is willing to apply logic to the claim that well design amps (based on specs and measurements) do sound audibly different when the compared amps are operating at well within their input and output limits.

Again, @TLS Guy has made it clear, the much improved sound quality he referred to so far about the AV7705/6 Vs AV10 is about DSP sound, such as Atmos, he has not said anything about audibly better sound quality for non processed, such as in pure direct mode.

That is true, although I think the improved SNR is a factor. I think the deleterious effect of noise is something that is underestimated. It takes little noise added to the program even if the program seems to mask it. I have always waged war on noise, which is why I am obsessional about the ground plane. So i do think the absence of noise from the AV 10 is a factor.

Undoubtedly though, the biggest issue is the improved Atmos performance with improved localization and much better preservation of the natural ambience of the venue.

My major issue is that I am highly trouble averse. Equipment failures are a huge PITA. I have found that in generally a high build quality tends to correlate with improved reliability. The AV 10 has not been around long enough to get a picture of its long term reliability. However, its build quality inspires a lot of confidence. The common denominator in my equipment that has been with a long time, is superb build quality with an orderly internal layout. If it looks like thrown together junk, then it probably is. Just one example, I have had a number of NAD units brought to me over the years. They are difficult to work on, because of layout/construction issues. People have, I think correctly said that NAD stands for Not Always Dependable. In my experience that has been a deserved moniker.

 

[Squishman]

I think you said once that NAD looks like a birds nest under the cover. I have a NAD cassette player that seems to be a pretty good one though. Mid-line for sure. Not a three head, but seems very solid after all these years.

 

[PENG]

I like your term ‘bottleneck analysis’. We should use this term more often to reach realistic common sense ground.

Some things that come to mind:

Cables – by the time we insert our majik cables in our home audio or HT system, the recorded signal has already been transmitted through up to hundreds of feet of non-majik cable.

Opamps – By the time we use an opamp or other kind of transistor circuit, a recorded signal has already been through up to hundreds of transistors in its path.

Passive components – Too large to fully comment but I’ll make a couple of comments. I see carbon composition resistors are in vogue in audiophoolery circles . I still have a whole box of ‘Wonder Caps’ They make you wonder. I wonder how many of these parts are in the recording chain...

Audiophile fickleness – We get easily bored and need to move on to the next toy. Occasionally we stop and listen to the music. I never get tired of Bach’s Solo Cello Suits. My current favorite is YO-YO MA, The Bach Project, Cello Suits J.S. Bach, From the Odeon of Herodes Atticus Athens. DTS-HD MA 5.1 recording. Complete with traffic and airplane noise. Signal to noise is probably about 40dB at best. When I get tired of every other piece of music, I put on a version of Bach Solo Cello Suits – or nothing at all.

Limits of knowledge – Most people can’t juggle 2 balls let alone all the ones in a multidisciplinary field.

Industry mysticism – the last thing the industry wants to do is fix real problems. It’s an IC – Industrial Complex. It’s sort of like the MIC – Medical Industrial Complex – that manages diseases rather than seeks cures. The major drug that the EIC – Entertainment Industrial Complex – dispenses is ‘Havitol’. Just do everything the industry says and you can havitol.

IMO this is a real winner rated post! It explains a lot, though never totally I supposed, why "all amps sound the same" and "all amps don't sound the same" are both a matter of "facts".

As mentioned (or alluded to), by the time our ears and brains get to even start working, perceiving, the signal, since created in the recording and mastering process, has gone through so many electronic parts, connectors, cables, wires, solder joints etc etc etc...., so from one of the numerous online dictionaries:

when trying to do a bottleneck analysis on the audio signal chain, from the recording mics through the loudspeakers or headphones, then to the ears and brains, one must keep the following in mind, unless one is able to ignore what I call "logic":

• A Chain is As Strong As The Weakest Link
• A Chain is No Stronger Than Its Weakest Link
• A Chain is As Strong As Its Weakest Link
• You’re Only As Strong As Your Weakest Link

Now apply to the bs claims of HDAMs, let me repeat my logic:

a) Marantz AVR and AVPs: HDAMs cannot improve slew rate (see definition on Sweetwater website):

Slew rate is the ability of a piece of audio equipment to reproduce fast changes in amplitude. Measured in volts per microsecond, this spec is most commonly associated with amplifiers, but in fact applies to most types of gear. In amplifiers, a low slew rate “softens” the attack of a signal, “smearing” the transients and sounding “mushy.” Since high frequencies change in amplitude the fastest, this is where slew rate is most critical. An amp with a higher slew rate will sound “tighter” and more dynamic to our ears.

So if the op amp before and after the HDAMs are the same as those used in the audio signal chain of the corresponding AVRs, as well as Marantz own AVRs but the low profile series, then even if the slew rate of the HDAMs are "infinitely" fast, it will not mater become it ends up going through the same opamps that have much slower slew rate (assuming Marantz if right about the much faster slew rate of the HDAM opamps (yes HDAMs are opamps, just discrete, not IC type)

-b) Marantz integrated amps: HDAMs in those will more likely realize Marantz claim on faster slew rate, because they are used in quite a few more stages, vs the AVRs/AVPs, where they are only used in the stage just prior to the final opamp buffer (again, yes, I saw it in the schematics/block diagrams of the SR6014 that I purchased when it was available).

c) as PaulBe pointed out, HDAMs, even just for one single stage in the AVRs/AVPs, will likely have different output impedance than units without HDAMs.

d) HDAMs, should in theory, if Marantz had chosen to, improve the pre out voltage SINAD at higher voltage when driving power amps that has relatively lower input impedance, that is, they could be more effective in terms of "buffering".

Overall, HDAMs unlikely has audible effects, that's probably why Marantz, since the AV10, and the Cinema 30 has included the selectable dac reconstruction filter, so that the user could select the default or the optional filter as follow (Marantz website):

What is a DAC Filter?

Marantz models such as the AV10, CINEMA 30, MODEL M1, and MODEL M4 offer a “DAC Filter” option within Audio settings. These DAC Filters adjust the roll-off characteristics of the audio signal.

• Filter 1 (Default): Recommended setting to enjoy the Marantz sound.
  • This filter has short delay slow roll-off characteristics.
• Filter 2: Recommended setting for bench test measurements.
  • This filter has sharp roll-off characteristics.

This particular claim while just a claim because "audible" or not is debatable and it certainly depends on the individual's hearing ability, or discernibility in the high frequency range as well as being subjective in nature, it is however, at least 100% logical, even when bottleneck analysis is correctly applied.

Bottom line, @TLS Guy has already confirmed the AV10 has superior surround sound performance, and is very audible to him, I hope he will try "Filter 1" and "Filter 2" and report back on whether he could easily hear a difference and then which one he prefers.

If I remember right, Gene said he could, or he thought he could? hear a difference and he prefers Filter 2 (NOT 100% SURE IF I INTERPRET THAT CORRECTLY FROM HIS TALK), that means he would have been just as happier with the Denon (A1H, A10H) sound too.

Finally, @ryanosaur , can you please also try Filter 1 and Filter 2 and gives us some feedback, thank in advance.

NOTE: Gene told us his preference between Filter 1 and 2 but he used the term that he prefers the one with the "wider bandwidth" so while I am somewhat confident he meant filter 2, there is an outside chance he might mean filter 1 because filter 1 will result in a roll off of about 2 dB by 20 kHz and about 2.2 dB at around 22 kHz, filter 2 will drop more at 22 kHz as it would act more like a brick wall at that point (ref: Nyquist criteria)

So at up to 44.2 kHz sampling, one can consider either filter as having wider bandwidth, I lean on believing Gene meant he prefers filter 2 because a) at 88.1, 96 kHz or above sampling, filter 2 definitely and clearly has wider bandwidth, and Gene mentioned it looked better on the test bench, since most bench test measure 20-20 kHz, and on that one, Filter 2's FR looks like a straight line vs Filer 1's roll off from about 12 kHz, so Gene most like meant Filter 2 look better on measurements. Marantz basically has the same narrative on that too:

Regardless, if @gene happens to notice my post, please clarify that your preference is in fact filter 2, or 1 (edit again: just realize in his review on this website he did make clear the one he preferred was the Filter 2), and thank you again for such in depth review plus a even more in depth review in the Youtube follow up video.

I would however, urge you to do another one when you have tried out DLBC, as I am quite sure you will get even better, smoother bass response with DLBC, with some minor tweaking. I am saying this based on my own extensive trial comparing Audyssey, ARC G and DLBC.