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@donavabdear hate to ask a dumb question, but the buzz does go away when you disconnect the audio input to the sub?

Why would @donavabdear downgrade from the Genelecs to the Focals?

With the right tools and parts why would Class D be any harder to fix than any other amplifier. It is rare for the amplifiers to fail. It is more likely the power supply fails.

@kota1 I do not want to speak for someone else, but my interpretation of the analog is that it is part of the process flow for mixing, as opposed to the now ubiquitous digital workstation. That would imply at least one additional digital to analog and analog to digital step in the process.

I am hesitant to talk too much about what the Trinnov does as this does not appear to be a receptive crowd. A quick summary. Trinnov comes from the studio world. Their product corrects the speaker response, and the room. It is two separate functions. Their integrated units adding the function of ATMOS and other formats, decoding and processing. It is used for playback. As it corrects the speaker, there are some obvious implications, I think, for the audio system that was described.

Please don't shoot the messenger on his first post.  I appreciate Brian's music, but there is a glaring incongruity in his position that I am surprised all the experts here have not noticed.

The MMThree / MMThree Exact is an active speaker. It has a built in 1000W amplifier to drive the woofers. The more astute will take note of the -3db point. 10Hz. The only way to do that with a box that small, small for 10Hz, is with an active system that increases the drive to the woofer as the frequency drops like many subwoofers do. Frequency correction is active speaker basics.

There is another incongruity that is pretty obvious, but this crowd is harsh, so I will let them figure it out on their own.

I feel I must further take issue with labelling any amplifier the best on its own. Amplifiers and speakers form a system. Colleagues would argue, correctly I must accept, that amplifiers, speakers, and the room form a system. No amplifier is the best amplifier for every speaker, and no amplifier is the best amplifier for every speaker and room combination. Tube amplifiers, even your Allnic, are often a poor choice for speakers where the delta from maximum to minimum impedance is large, and the minimum impedance is low. That amplifier could impact a significant and negative character on a speaker that a much lower cost SS amp would not.

Fact is @brianlucey, that your MMThree Exact is an active speaker, and you don't seem to understand this. The woofer section is powered, and shapes the frequency response of the amplifier to enable a very low -3db point. Your primary monitoring speaker is an active speaker. That seems to negate your views on active speakers.

For the Trinnov processor, one of its primary functions is to measure and correct the speaker response. It injects test signals and measures from its output through your amplifier, through the speaker, to its measurement microphone. It then corrects frequency errors, and phase errors of the combined system. It does this independently of the room correction function and surround decoding. A similar process is an aspect of a fully active speaker, but the manufacturer can do it more accurately as they don't have environmental interference in their measurement, worry of component drift, i.e. from a tube amplifier, and then can directly control each driver, not just the system as a whole.
 

Perhaps my expectations are too high to expect adults to tone down the insults and chest pumping, and discuss this subject in something other than falsehoods and misconceptions, a subject, you may guess, is near and dear to my heart.

@brianlucey please do not emphasize on incorrect. The MM3 is an active speaker. There is absolutely no denying that. In this case, only the woofer is an active system, but it proves out it works, and it is superior, even in what are, in your estimation, some of the best speakers available.

You are mistaken about what a Trinnov processor does. My idea of correction is not false. Let me repeat your own words to you,

The Trinnov is the most powerful piece of equipment that anyone could ever put into an Atmos studio because it deals with so many elements so quickly. It deals with the measurements for distance, adjusts the 3D placement, improves phase, group delay and speaker amplitude linearity, plus it upgrades the room issues. Beautiful results quickly, and more than physical measurements and treatments alone could accomplish.

The Trinnov has no concept of the speaker on its own, but the speaker with its connected amplifier and anything else in the signal path. The Trinnov corrects the things you mention, phase and frequency response of the combination of your amplifier and speaker. As I wrote above, that is what an active speaker does, but can do it more accurately. Everything else the Trinnov does is layered on top of the speaker correction. These are your other words,

But if you’ve done all you can with the physical side, then you bring in the Trinnov and it’s really quite remarkable, especially for speakers with a traditional crossover. I could not live without it for my Atmos room.

I am sure you will agree that your main speakers, as they correct the response of the combination of your amplifier and speakers, will not sound the same, on their own, with the Trinnov in and out of the system?

You don’t seem to understand, in detail, what that Trinnov does. Even in L&R Mode, it is applying corrections at the speaker level.

https://www.trinnov.com/en/blog/posts/trinnov-optimizer-features-according-to-l-r-excursion-curve/

FULLY ACTIVE SYSTEMS WITH DA AMP CABLES SPEAKER DSP IN ONE TEND TO BE A COST ISSUE COMPROMISE.

May I ask how many fully active speakers you have developed over your career? You appear to be stepping far out of your area of expertise. Even your MMThree are a cost compromise. For the implementation of DSP, D/A, amplification and power supply, in many situations, we would be hard pressed to make it cost more. For these sub components of the design we could add frivolous components that would increase the cost, but they would not improve the sound and hence would not generate a resale premium to our target professional markets. These sub components are not the limiting factor in the SQ of our products. That will still be the driver components and cabinet / acoustics for the long foreseeable future.

One observation I will make about brianlucey and donovabdear is that the markets they serve have much different requirements where consistency and subsequently accuracy is concerned. For music, mixing or even mastering with substandard SQ or highly musical setups yields good results as the target playback devices are diverse and lacking standards and you don’t have the criticality of dialogue. For movies, the opposite is true. There is high consistency in playback in theaters, and even home systems due to automated room correction. Not only is there high consistency, but there is an expectation of consistency and a need due to dialogue. Brian’s musical amplifier and speaker combination may not cut is in donovadbear’s world. Our market intelligence suggests ATMOS and related formats driving music towards more accurate systems over time.

@donavabdear / @brianlucey 

Are you hearing any rumblings in regards to a heavy push on concert pay per view, both delivered in specially equipped theaters and for home?   Our growing world means far too many large markets for performers to perform in live, with tickets at those events exceeding the budgets of most fans.

What’s left in regards to fitting an amp section with a driver ditto can as well be handled with the careful choice of an outboard approach, with even better amps and what fits a given listener’s preferences and specific acoustics to boot.

One issue is that all speakers (that I am aware of) designed to be driven with an off the shelf amplifier have a cross over that cannot be bypassed to directly connect to the driver. Hence any external amplifier is handicapped by the crossover.

Two would be the assumption the interface to the driver is a simple set of wires. Think of servo controlled subwoofers. They require a direct connection to a special amplifier that has additional feedback inputs. No simple external amplifier is going to work and the amplifier needs to be tuned to the speaker for best performance.

Three would be an assumption that a simple voltage driven external amplifier can achieve the best performance out of a driver, even if you were allowed direct connection to it.

Four would be the assumption that all drivers covering a similar function in a speaker are all going to do the same thing at the same time with the same frequency response. Even a one way speaker, can have multiple independent elements.

If your perception of an active speaker is just a passive speaker with a similar style amplifier in the box, with the crossover likely at the signal level instead of with big passive components at the speaker level, then making the assumption that a traditional speaker with an external amplifier can compete is a fair outcome.

The people working on the leading edge of active speakers are not making that assumption.

"Activeness" can be applied to any system just by the addition of the right processor like the new DEQX units or the Trinnov Amethyst. Then you have the ultimate control over what your system is doing.

You have full control over your system, but not over the drivers in the speaker.

Yes, you do have full control over the drivers - if the context implies the omission of a passive cross-over with dedicated amp channels looking directly into each driver section. Any "next level direct driver control"-claim (my own wording) essentially put forth by the bundled active speaker manufacturers, if it were to distance themselves from a claimed inferior outboard solution, actively configured as well, would seem dubious to me, whereas they would be right to do so with a passively configured speaker by comparison.  

@phusis , I am not sure we are understanding each other.

I could put the active portion of the speaker in the speaker or in an outboard box. That much is obvious.

What I can't do is replace my electronics with anyone else's electronics. As noted, the connection to the driver may require 4 wires (or more), and only I, the MFR knows the intricate details of what is needed to optimize how that speaker element is driven and I won't be sharing that. That is I/P.  The other case I noted is multiple similar elements being driven to accomplish a specific function. That is far more than just adding some external amps to replace internal ones. It is like saying just give me the car, and I will put my own engine in at that point.

You're making it sound as if using external amps in an active configuration, certainly in my case, is a careless and crude affair, but that's really only assuming the worst of it while promoting your own business of an inboard solution as that which harbors the best of active. 

Careless? Not at all. Crude only in a comparative sense. I don't think you are understanding the variables that are available though for active speaker implementation. I don't expect a hobby implementation to compete with a large R&D budget so don't take offense. 

And someone's ego grew three sizes that day. 

@donavabdear do you have a room response comparison for your two systems?  I would not be surprised if the difference is more frequency response than anything.

One issue is that all speakers (that I am aware of) designed to be driven with an off the shelf amplifier have a cross over that cannot be bypassed to directly connect to the driver. Hence any external amplifier is handicapped by the crossover.

From several pages ago @lonemountain ​​​​.  However that's not to say you may not still have some larger passives in the drive circuit of an active speaker but they are part of an integrated solution.

Obviously @brianlucey likes his DACs, amps, and speakers, and how they are connected, but they are but one combination and even assigning a ranking, like 3rd best DAC made or best amp you can buy is purely one person's opinion, no matter how experienced they may be, they still have their own conditioning and biases that influence their choices. They may be great speakers, but would they meet the criteria of accurate? I honestly don't know. I know the Allnic amplifier cannot be neutral. It must, by virtue of its design, impact a unique sound that other amplifiers may not or will not.

Many active speakers are designed to offer a low system cost. Professional sound reinforcement are active for reliability and ease of use. The highest end professional monitors are active for accuracy, dispersion, and consistency. An expensive external DAC or tube amplifier will not make them more accurate, it will make them less. They are not the bottleneck. Next generation active speakers, professional and consumer will make further strides in improved accuracy, and continue the trend on the consumer side of dispersion control.

It is a philosophical difference of approach. If I add something to the sound, some may like it, some may not, it may work in some situations, and not in others. Some things I add can be taken out by external processors. Others cannot. Some things can be accomplished with external processors, and acoustic treatments, others cannot. If I provide the customer with something that has inherent accuracy, that has as few warts as possible, and is even flexible in how it radiates the sound, then I am giving them a canvas and brushes to paint the picture they want, not the one I want to sell them.

@steakster, no, I can't tell you if I want to keep my job, or at least not have to experience the wrath of my boss.
 

@juanmanuelfangioii , I have already contact the mods about others who are promoting this lie. Do I add you to the list?

@donavabdear ,

You use monitors that are accurate. Cinemas are professionally set up so there is some level of consistency from cinema to cinema in term of frequency response. You can't assume that with consumers. You are working from a flat response so the only deviation in perception would be your own ears. The customers system may not be flat or accurate but the deviation is only from the flatness of your system and your ears.

If you were to mix and master with a system that was pleasant to your but not accurate, wouldn't that compound the deviation a customer would experience? And that's just you. If someone else doing the same job had a different preference of setup and tuned their working environment system differently couldn't the end result at the customer be a complete swing in tone?  That sounds like a formula for added variability when the customer is looking.

Wouldn't that contribute to why some albums sounds great and others do not, but someone else may have a completely different view?

1. Each driver is optimized by its own amp
2. Better transient response
3. Amp dampens the voice coil perfectly
4. Amps designed for impedance of the driver
5. Amp is directly connected to the driver
6. No loss between amp and driver
7. No crossovers after the amp
8. No speaker level crossover design problems
9.  

• These are all essentially related so I will address as one unit.
• Yes, the amplifier can be optimized to some degree, but for most active speakers, it is just an integrated solution of external boxes and moving the crossover. That is 1^st/2^nd generation active speaker design. Next generation designs employ more sophisticated amplification electronics that cannot be replicated by a simple external voltage amplifier and never with a passive crossover.
• Missing from this discussion is not only can the amplifier be optimizing, but the driver that is used in an active design can be optimized for an active configuration. Drivers today are designed to be linear with voltage drive. That is not ideal for optimum performance but does make passive crossovers easier to design and performance more consistent.
• A basic connection of the amplifier to the driver does not damp the voice coil perfectly. The resistance and inductance of the voice coil prevents that in a basic voltage drive implementation

9. More accurate than random amp / driver combos

• I would not say that is an inherent advantage as most amplifiers will drive a speaker accurately when that amplifier behaves as a voltage source. The accuracy comes from the tight integration.

10. No speaker cables

• Not touching that one

11. Amps designed for proper power handling of driver
12. Amps are more efficient designed for a smaller power window
13. Amps can be up to ½ the power (lest cost more reliability)

• These are true to a point, but we also have multiple amplifiers, potentially increasing standby power. Do we have 1 power supply, multiple? Does it matter?
• I don’t think it is the amp designed for power handling of the driver, but the amplifier knowing the power handling of the driver and can henceforth ensure it is protected from damage.

Comments are being made about the quality of parts built into active speakers versus external parts. I know this is a touchy subject, but when our higher end active speakers are considered, the quality of our internal DAC never enters the discussion for us. If we improved it, no one would know as the performance of the drivers is the limiting factor by a large degree. To meet marketing requirements, we are implementing the common consumer filters on some models which you may be able to hear if you feed it 44.1 or 48. Across the price range, the amplifier quality scales so that the driver is always the dominant sound unless you are driving them harder than they are designed for. The only time DAC performance is evident for us is on next generation and R&D designs as we need to grow our own. We need much higher conversion speed and less latency than integrated solutions.

@mijostyn ,

Your setup a a good example of where an active speaker could provide benefit. A sub-woofer designed to compliment your speakers could use multiple drivers to create a shaped emission that matches your main speakers more closely. Could you do that passively? Perhaps, but it is much easier to do with DSP, and it is more flexible. There could be options for programming the listener distance to better shape the response as the speaker transitions from line source to other, etc.  Similar to how external DSP can not fix all room issues, it cannot fix all inherent speaker issues either. At the penultimate, a sophisticated active solution could shape the drive signal for the panels to extend dynamic range.

@donavabdear, there are several ways of getting around the impedance issue that I am aware of, either include the magnetic components in the feedback loop or compensate for the impedance in software or hardware. Companies are building patent walls around this, or trying to. For the lowest cost the phase shift is there, but can be contained, as you control all variables, so that it is not an issue. At the high end, buy modules that don't suffer this issue, pay licensing fee, or build  your own technology that will stand up to a patent lawsuit, or have a couple in your back pocket related so that you just cross-license.

@donavabdear , one area of ATMOS you could probably enlighten us on is the relationship between microphones and ATMOS objects works. When you are mixing, i.e. creating, you can place a sound wherever you want. However, for what you are doing I assume there is an aspect of capturing it as it happens. I would love to hear your perspective on that.

@steakster , have you noticed that with the exception of small boutique brands, no one from any supplier obviously participates in audio forums with rare exceptions where maybe there is a supplier corner? There is a reason for that. No matter what you say, you will make 50% of the people unhappy. Most companies have either formal or informal rules against it for any of their customer facing or senior staff. That is the situation I am.

As well, it would be wrong for me unless I was a paid advertiser to advertise who I work for and hence our products.

@audioman58 , by what definition do you define reference level? Popularity? Lots of write ups?  Many many people do not like B&W speakers, not even the 801. As a speaker guy, there are some excellent things about this speaker, however, I always feel like they got it to market before they finished it as they always seem uneven in the upper treble. Maybe in a few years I will no longer care as I can't hear it.

What do you think Bricasti amplifiers do that cannot be done in a power speaker. This is where @donavabdear 's comments come in. A class- D amplifier can easily keep up with the Bricasti for the bass frequencies, and then a good quality A/B amplifier would have no problem matching for the mids and high frequencies, both perfectly matched to the drivers they are connected to.

The 801 has almost too wide a dispersion for many home installations. It has a lot of energy off axis which can result in it being viewed as bright without adequate absorption. This is a common complaint. The Genelec is tuned to be near ideal for many installations. Most Genelec would require a sub to compete for bass frequencies and level. I expect the distortion of the best Geneiec equals or is lower than the B&W Bricasti combination. Less distortion, less lost details.

@kota1 , that is a strange conundrum, faithful to measurements, but untreated room. Dr. Toole had his omnidirectional speakers in an untreated room too, but his room was very large. That works in a large room where the reflections are delayed. Amir's room is small. Too each their own. His focus is on signal integrity including what comes out of a speaker and debunking.

Sorry no, @ronboco. It is likely you know of the company.

@mijostyn, Atmos overcomes limitations in 2 channel reproduction that are inherent in the format. Very poor ability to position sounds being the primary one. 2 channel could be considered a subset of Atmos. Atmos add the ability to capture and reproduce more of the complexity of the sound in a live venue, and adds addition creative elements to studio productions. The downside is using likely like 3D in movies, using it as a gimmick and not to enhance realism.

I can make your system sound way better by using outboard amps and digital processing/crossovers.

Perhaps this is true in this specific case as these are old designs. However, it ignores the tight coupling of application specific amplification with the drivers. Using external amplifiers, no matter how good, does not address this.

@kota1 '

Paradigm, Anthem and Martin Logan speakers are all owned by the same company.

@donavabdear , it is amazing what near perfectly flat speaker response on-axis will do for imaging. Don't let the room screw it up and you are golden. This is the flaw and the trap people fall into thinking they can use room correction / DSP to fix the speakers. The accurate imaging with speakers is almost always near field with a perfectly flat speaker response.

Big disconnect w.r.t.. knowledge, specifications, and setup to achieve imaging. So many "ideas" about how to place speakers, toe-in, etc. without those people having a good understanding of what is under the hood and what is happening. (Not saying you).

371A is -6db at 23Hz. It does have a potentially high cutoff as it is not intended to be an independently positioned sub but integrate as the bass section with The One series speakers. The high cutoff is to improve integration as a stack and allow flexibility in directivity. It has two drivers, the smaller one, by necessity, is at the top close to the higher frequency drivers of a stacked unit on top for proper integration. The larger driver handles the deepest base.

It’s 134lbs plus whatever is on top. The reactive force from the motor in the top driver will only marginally move the enclosure. Any resultant sound from that will be so far down it will be totally inaudible. The only concern is a mechanical resonance but Genelec is hardly new to making speakers. The "Newtonian" forces are relatively low and less than most think. The cabinet will only vibrate if poorly designed. Dual opposing woofers makes for much better marketing than improvements in sound. There will be things audibly vibrating in your room, but it won't be your speakers.

Many flagship speakers are WMTMW with a large woofer on top.

@rick2000 , many people could list their speakers, cables, dac. and amps for sale, take the cash, buy a set of Dynaudio Focus speakers, get an upgrade, and have money left over. I think they won't because it is too hard to let go of the OCD that often comes with this hobby. Fortunately their is a new generation getting into this hobby that will benefit greatly from a plug and play, value priced ACTIVE system like this.

Much of the hobby survives on the satisfaction people get from spending money. I don't know if that is variety is the spice or life, or whether people need to feel they are moving forwards even if they are moving sideways or backwards.

@donavabdear ,

@thespeakerdude I wanted to ask you about WMTMW it seems to not make sense but as you mentioned there are many great speakers that use this. Seems like the low and mid frequencies would interact a few feet out. no one would ever use a microphone setup in that form there would be to much phasing.

We obviously test a lot of our competitors, but these companies are not our competitors, so we would never test them, not to mention too expensive to purchase and tear down!

I expect how they behave is, like all speakers, room dependent. Over a range of frequencies, it should help with vertical room modes and since people are least likely to treat the floor and ceiling, from a practical standpoint, that could be quite a good thing. It's not going to replace multiple subs for room averaging, but it may help a bit though my mind says watch for peaks and valleys with varied ceiling height.

With all the variety in our head shapes, I am not sure how any headphone can sound right "out of the box". Speaker and room to me equate to headphones and head.

There is an old rule in recording called the 3 to 1 rule and it means the distance between the source and first mic is 1 the next mic should be 3 times that distance if you want less phasing.

To me, this rule (guideline) would factor around the typical fundamental tones of what you are recording, with the fundamentals being much more narrow than the extent of harmonics. With a speaker, and each driver working over a defined range, pointing in a specific direction, with the listener assumed to be at tweeter level, the problem would be more bounded. Remember MTM falls apart in the vertical direction if you are too far off axis.

Hence bracing, The large the panel dimensions, the greater the bracing. A superior shape is of little benefit if we cannot manufacture it, added shipping costs ameliorate the benefit, or it causes difficult in use for the customer. FEA allows easy and quick analysis of designs.

@phusis , the main issue is that most of my customers are not willing to expand the size of the control / mixing / listening rooms to accommodate the required size of a horn subwoofer in order to get a sufficient efficiency boost at the frequencies the subwoofer is expected to cover. Even for a subwoofer I need to be careful about dispersion as well.

They may go down to 32Hz, but that is probably with drop-off and high distortion, and if using 2, more room mode excitation. Subs are to reduce distortion, go deep without roll-off, and reduce room mode excitation. Ideally you cross your speakers higher so they are not taxed with frequencies/excursions where they distort.

Sorry @lonemountain but high passing mains,. especially residential is often the right thing to do, and done right, with quality subs and filtering on both is inaudible. There will be no shift in tone and no localization is possible.  You have to be cutting off below the Schrodinger frequency. Your subs have to be low distortion, especially anything third order and higher. That may be as much a consideration for where you're cut off frequency is as anything.   If you've got large means that can play low distortion at high volumes at base frequencies, then I would consider it beneficial to run them full range. But most mains these days don't fit that criteria. For most means I would far prefer a cut off that's not full range especially if the customer likes high volume levels. 

I don't understand your comment with respect to DSP. With any modern half decent quality ADC, you're not going to hear any sound of using an ADC and then DSP. And of course if it's an all digital system, it's a nonstarter. Talking about DSP delay is also not relevant when you bring up in the same paragraph 180° out of phase operation which is a delay. There are no absolutes speakers like a line array can be difficult to integrate with subs and an evaluation needs to be done based on mains speakers, room size, listening levels etc

Apologies I used voice dictation for my last post and it changed mains to means several times. So much for context sensitive dictation :-)

@lonemountain if you are low passing the subs at only 2nd order (12db/octave) then you pretty much have to run the mains full range. Even 24db/octave is not enough with a high cutoff if you want to prevent localization. Analog filtering on the subs can often cause phase integration issues with the mains. 2nd order will have less phase issues, but has the aforementioned issues. DSP filtering is by far best for subs.

@mijostyn - Corner loading a sub may be the best option for a room, or it may not be. If it is bad for a given room and that room has symmetry, you quite often create more problems than you solve. It would be far more often the case with two subs that pulling them forward on the opposing walls out of the corners would result in more even bass and better use of available power. Your subs will only have some limited line array effect as the line is wall-to-wall, and the floor is right there, so you already have one immediate reflection, but if it behaves as a line array, the front wall-back wall room mode is amplified. Your crossover is below the Shrodinger frequency.

@mijostyn , your bass "line array" goes from left wall to right wall, well in theory, and includes the walls as reflectors to extend the virtual length of the array (again in theory and needed for low frequencies). The floor is still a first reflection point, though it barely matters since your subs appear to be working purely below the Schroeder frequency (again, thank you Google!). Thinking of it as a line array is giving you an inaccurate perception of how the bass is behaving in your room or any potential gain advantage beyond room gain.

Talking about late reflections (or early reflections) in bass has little practical relevance. That is not how we hear bass. You cannot decouple how we hear from the acoustics. Also when talking phase, it is important to clarify phase during cross-over so you don't introduce an additional peak or null during transition at the listening position. However, back to Shroeder frequency and real rooms, we are never dealing with single waves with bass, we are dealing with mode dominated spaces. The coordinated arrival of first waves from the various drivers is less critical than how the modal field develops, in the typical room that is not able to damp bass much at these frequencies. That is why bringing the subs out along the walls into the room often works better. The reductions of peaks and valleys from modal excitation is less critical than first arrival phasing which you cannot hear.

@donavabdear

Quick Google JL Audio Fathom f113v2 and hum. Common problem. Nothing to do but get them serviced.

@mijostyn feel free to put your opinions of how acoustics work above actual knowledge. It may make you feel better, but it will not help your understanding. You may have a basic conceptual knowledge of line arrays, but you are both not applying it correctly to your situation and not understanding that your situation does not apply.

You may want to dig a little deeper into line arrays and understand you are neither operating free space, nor at frequencies high enough that the side walls result in a virtual extension of your array:

https://www.merlijnvanveen.nl/en/component/phocadownload/category/3-documents?download=76:line-arrays-theory-fact-and-myth

No need to rewrite what others have spent a good amount of time already explaining. René knows his stuff. You may want to read his comments in other spots on DBA and plane wave in a tube.
 

https://www.audiosciencereview.com/forum/index.php?threads/analytical-analysis-room-gain.23211/

@mijostyn , you have two people @donavabdear and me, who work professionally in the field, both apparently with physics backgrounds. As well I (and apparently @donavabdear) have worked with other physicists, acoustic experts (often physicists) and engineers who also have significant expertise. I provided you with some links that explain, at as basic a level as I could, that what you think is happening and what is happening, are not the same. You can do with that as you wish. You can try to increase your knowledge, or not. Your choice. People often minimize the complexity of things they do not understand. I am sure you experience that in your own career.

I guess it's a good thing I got a math degree before physics.

@kota1 ​​@mijostyn ’s main speakers are floor to ceiling line sources. He does not need to worry much about floor and ceiling for them and side wall reflections are likely to be a bit lower. Still have floor/ceiling and side walls for bass as the subs are omnidirectional at those frequencies.

@donavabdear since no one final masters in a perfectly flat room and mixing highly nearfield is the only thing that comes close why would you want to playback flat?

This brings us back to the original topic. You do want the direct sound perfectly flat if you can. Active speakers do that better than anything. That gives you a great starting point. From there do your room acoustics and subs to get close to your target non flat in room curve. Finally DSP to soften anything really off. Room correction has to make the on axis non flat to correct the room. Modern processors try to understand what is direct /reflect so they don’t over correct but it is not easy.

@ricevs we have had direct digital amps for quite some time. It sounds simple but is not. A DAC does not need feedback. Amplifiers generally do. Direct digital and DAC/AMP each have their advantages and disadvantages. Direct digital amps are single bit so far. DACs are multibit. The math in a multibit implementation allows more tolerance for the engineers to do their stuff. Does it matter? No, both can be transparent. Same with silicon and GaN. Silicon can already be transparent. GaN could make for nicer but meaningless specs. For us we like the reduced packaging/heat sink requirements GaN may offer.