“You Are There” Absolute Sound: Can We Get There From Here? Part IV

sbnx

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More on the monophonic testing paradigm Toole adopted:

The fact remains that speaker performance measurements are mostly all done in mono. That is the almost universal practice. It is thus entirely reasonable that subjective performance evaluation of speakers, especially subjective evaluation of frequency response smoothness/flatness, distortion, and dispersion, also should be done in mono. The burden of proof should not be on Toole to prove the reasonableness of his procedure. The burden definitely is on those who would dispute it. Toole adjusted his testing protocol since he noticed that mono listening produced a higher and more consistent ability to distinguish among speakers' sound quality. That is a truly scientific method--redesigning a test for higher discrimination on the variable under test. Likewise Toole eliminated the variable of hearing acuity because he noticed that those who did not test normal on standard hearing tests were not as discriminating or as consistent in their judgements of frequency response, distortion, etc. as other listeners.
Regarding Toole's use of mono to assess "sound quality". I believe this it is also experimentally best to use only one speaker as it removes the variation in frequency response that one gets from variation in the positioning of two speakers relative to one another. If a stereo pair was used someone would argue that a panel of listeners preferred speaker A over speaker B because speaker A was positioned better or more accurately.
 

tmallin

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Now that I have that discussion off my chest, I want to discuss a couple of things I view as "obfuscations" of current high-end audio.

Obfuscation #1: Viewing inaudible and usually unmeasurable "noise" as so important that failure to take extreme steps to minimize it will result in your home audio system falling far below its potential and in fact arguing that the failure to minimize of such "noise" is the most important factor standing between home audio listeners and audio nirvana.

I suppose it is inevitable that once measurable noise and distortion of all types is brought to levels which are a small fraction of one percent, manufacturers of all types of equipment will begin to argue that their equipment is superior because it attacks in some novel and more effective way some sort of distortion or noise which they speculate is THE problem. Oftentimes, this problem is theoretical and could really happen, but the measurements or listening tests showing it is truly audibly significant often are slow to come or never come. However, audiophiles, being a rather desperate (for that next increment toward sonic perfection) and gullible group, jump on board, spend large sums to fix this supposed problem by using the manufacturer's device, and then trumpet that, yes, a thousand veils are lifted, etc.

I must confess to not being immune to such appeals myself. I'm as guilty as many other audiophiles in trumpeting sonic improvements from things like power filtration and mechanical isolation devices. You need only look at my threads involving the EVPs and P. I. Audio devices to see that I've made what I now recognize--months or years down the road from those "discoveries"--were exaggerated claims for the efficacy of such products. Yes, such things can make a positive sonic difference. But in the grander scheme of things, the improvements and differences they make truly pale in comparison to those made by simple acoustic changes, such as moving the listing position or speaker positions by an inch or two, applying a bit of electronic equalization, or changing the acoustic treatment of the surfaces of your listening room--much less changing speakers!

Yes, most everything you do to a stereo system can make an audible difference and sometimes those differences can be classified an a true improvement. But the Big Things remain the Big Things and most people on both the professional and consumer side of things haven't got them right yet: microphone frequency response and pick-up pattern, the number and set up of microphone during recording, room acoustics, system set up, and frequency response/directivity of the speakers used. Transducers and room acoustics are the main things.

For some of these devices, yes, you can make measurements which show differences. For example, the videos of the EVPs in action show how they damp sonic chatter at the source and the measurements show how transmission of vibration is reduced fairly uniformly with frequency. But how this vibration absorption translates to audible differences coming from the isolated components is not demonstrated. I daresay that there are few if any measurements showing that the vibration of an electronics chassis interferes with the measured frequency response, distortion, or noise from the output of the electronic device at any frequency within the audible band or substantially outside that band. Whatever differences/improvements are heard must necessarily be quite small if none of the traditional measures of audio quality are affected. Move a speaker a couple of inches, however, and you will measure clear differences in its frequency response of a magnitude well above the threshold of audibility.

Similarly, the P.I. Audio devices do show a difference in measured line noise via a line noise "sniffer" type device. But how does such line noise get through the power transformer and into the output of the electronic device when the output of the device measures the same in terms of frequency response, noise, and all types of measurable distortion regardless of whether the P.I. Audio device is used? Again, the audible effect must logically be very small indeed.

And then the folks claiming the importance of the reduction of such noise totally ignore the much higher noise floor of the recordings themselves. Highly prized analog recordings seldom have a signal to noise ratio exceeding 70 dB; for the earlier Golden Age recordings, it's more like 60 dB or less. Even CD-quality digital recordings theoretically have noise no lower than 96 dB below full output and the air handling noise in recording venues frequently exceeds that level. Distortion and noise can be measured down to at least 120 dB below full output and the addition of mechanical or electrical filters of the type I mentioned will not show any noise or distortion reduction even when measured down to that level.

Clearly, reduction of such "noise" is not a Big Thing.
 

tmallin

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Obfuscation #2: Using YouTube videos of amateur recordings to demonstrate the sonic quality of anything.

YouTube is ubiquitous; I know that. But I think there's a danger that audiophiles and music lovers generally tend to accept what they both see AND hear on YouTube as the gospel truth.

Sure, it's fun to watch those reports from audio shows with recordings of this or that room's system in action. And audiophiles around the world now seem to record the sound of their systems in their video. Sometimes such videos are used as part of a sales ad to show, I suppose, that, yes, the speakers I have for sale do in fact play music. Or music lovers post bootleg recordings of concerts to give viewers a taste of the experience. Often times, though, I think this is just an example of audiophiles wanting to show off--show off the look and sound of their equipment and listening room.

If that were all that's happening, I wouldn't be so worried. But the tenor of a lot of these videos clearly is intended to demonstrate the sonic quality of the speakers/system or concert recorded. Viewers should not take the bait.

Unless the notes to the video provide such information (rare indeed!), you have no idea what microphones were being used, where the mics were placed, the true subtended angle between the stereo speakers captured at the microphones' recording position, whether any equalization was applied to the recording, etc. You probably won't even know the exact version of the recording you're listening to, making comparison with the sound of a version of the recording you have available in your library more difficult.

Often it seems such recordings are made with a smart phone's stereo microphone. Sometimes the sound clearly varies with the video as the recordist moves around the room showing the speakers from various angles. Other times the perspective seems stable, but that opens the question of what kind of microphone array was in fact used to make the recording. You usually have no idea about the quality of the microphone. Cheap microphones often roll off the bass and extreme highs and have upper midrange and lower high frequency peaks. You usually have no idea whether any attempt is made to equalize the microphone response.

Sometimes you can figure out what version of a recording is playing. That happened, for example, with the Dave Brubeck Take 5 Outtakes album linked to in a prior post in this thread. As far as I can determine, there is only one version of this album. I then compared the sound of the YouTube video with the sound of a local or streamed (via Qobuz or Tidal) version of that same recording at the same volume level through both my speaker-based system and a headphone-based system. Even then, however, the stereo perspective captured in the YouTube video likely won't match the perspective from the streamed or local version, and you will hear the tonal colorations of the microphone used to make the YouTube video compared to the intended frequency response of the recording from you local or Qobuz/Tidal streamed version.

So, beware. What you hear from YouTube sound may bear little resemblance to what you would have heard live in the room where the YouTube recording was made. Resist the temptation to make any sonic quality judgments from YouTube videos.
 
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KostasP.

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Chasing ......uncatchable birds

Hello tmallin from Melbourne,

I appreciate your genuine, unpretentious and passionate approach to this hobby and the excessive time and effort that you selflessly put into posting your thoroughly thought-through comments and experiences.

What I want to say is that recording, as a process, is a complex function of many variables, of which science and art are the most prevalent ones, and the average audiophile will ultimately judge the final product by sonic and\or musical criteria, regardless of what means or techniques were used to achieve it. Often the more convoluted, heavily manipulated productions paradoxically seem to be preferred ( from a sonic, not musical point of view ) to the so-called pure, minimalist and fastidious recordings. It is more than just compression and multi-miking; it can be a serendipitous mystery of the art itself!!! Let me explain.

I have recordings from MA Recordings, TRPTK, Tonianlabs, FIM, 2L and others. These labels are known for their quality recordings. I have directly communicated with the owners of MA, TRPTK and Tonianlabs ( and even Winston Ma of FIM ) to discuss their approach and philosophy in relation to their pursuit for the ultimate sound. I also have many direct-to-disc vinyls and of course truly high quality CDs, SACDs and vinyls from a variety of other labels. I myself use a high quality recording system ( AKG matched pair of 414 XLS microphones, Millennia HV-3C pre-amp, Tascam DA-3000 Recorder ) and record a variety of acoustic instruments in my dedicated listening \ playback space of approximately 50 square metres ( 5.5 x 9.0 x3.0 metres ). I employ a variety of recording techniques depending on the number of musicians, without compression and post-recording mixing and mastering. I mix\ master "naturally" by placing the musicians judiciously around the mikes based on the dynamics of their instruments. There is NO post-recording processing at all and I listen to my recordings on my main system in the same room.

Why mention all the above? Quite simply and humbly, to say that excellent recordings in the general domain of the recording industry are made regardless of recording approaches and proclamations of purity and superiority! I do NOT proclaim that my recordings are superior to any others, nor do I like all of the recordings of the above-mentioned labels ( and I have about 50 such recordings ), despite what their owners claim! Often I envy many of the conventionally produced records. Purity of sound is beguiling and alluring but it is not everything and it is certainly not the only method to attaining high quality.

Despite what many on this forum proclaim, acoustic instruments are not so warm and thickly textured. They may be warm and "thick" from a distance in a hall, because of the reflections and reverberations BUT directly from a metre or two, they are not ( and often not vey sweet either )! I play a number of them and so do my children. Quite the opposite; they tend to be light and airy with a weight commensurate with the size of the strings and the body of the instrument. The same with the human voice. One should not conflate these descriptions with frequencies. A low note may have weight but will retain its "bounce"; it will not be thick and slow. Non-linearities in the system and the room will most likely produce this artefact.

It is "therapeutic", sanity saving and very re-assuring to assess our listening experiences as audiophiles once we have had direct experience with high quality home recording and studio productions ( I have done some mixing in the past ). Once you acknowledge and accept the limitations, complexities and personal choices nvolved in the recording process, then you longer expect your playback system to turn a "crow" into a "nightingale"! Compare the unimpeded vividness, naturalness and vibrancy of a direct mike-feed musical signal to its stored counterpart and you will know. What you strive for is the achievement of proper, relatively high quality THRESHOLDS within the various components of your playback system, without pathologically obsessive behaviours with the peripherals. Example: I place my ear right on the speaker with a volume level that will give me SPLs of 105 to 107 dBs ( Fast, C-weighted ) and it is dead silent...Should I obsess with noise floor levels?!

All we can expect from our systems is the reproduction of flawed recordings, played on equally imperfect systems that meets our REALISTIC criteria and these will vary from person to person. I value transparency, resolution and linearity which ultimately lead to a more accurate rendition of the recorded tone, timbre and micro inflections. My system, based on electrostatic speakers, placed judiciously ( at least 10 ms delay from all boundaries ) in a room which is conducive to good sound comes very close to satisfying these criteria and my own recordings overall are a testimony of my achieved goals. I equally, if not more so, enjoy hundreds of others without self-illusions about "Absolute Sounds". If a system has the hard to define synergistic pulse, able to give you a tactile sense of the recorded venue, then it is time to stop ( as we say in Greek ) chasing.... uncatchable birds and to stop looking for black cats in a black room.

Be well and continue maintaining your passion. Cheers, Kostas.
 

tmallin

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Thanks for you comment, Kostas. If you are recording musicians in your modestly sized playback space (this is what I understood you to say), then of course the sound you hear and the sound your necessarily close-up microphones will capture is quite different from the sound one would hear in a concert hall. You will hear more highs, more immediacy, more detail and the sound will not be "thick" due to the distance and ambiance typical of hearing musicians at a distance of 40 feet or more away, as typical from even the nearer rows of a concert hall or other large venue.

For many years I have attended a series of living room classical music concerts in the home of a friend. The room is a large living room with unusually favorable acoustics (lots of diffusion from heavy timber, stone, and brick construction plus picture windows in a corner behind the concert grand Steinway), not much different in size from what you describe. I have heard musicians in various chamber ensembles in that room from less than three feet from the violinist's bow to maybe 20 feet away. I totally agree that this can be an enthralling music listening experience and also totally agree that the sound differs from concert hall sound in the ways you describe. It also tends to be much louder than one would hear in a larger room from a distance and that can be thrilling. It doesn't sound like classical music in a concert hall, but it sounds really fine and not at all sharp or shrill like so many closely miked commercial recordings heard on your average home audio system.
 

tmallin

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It is quite easy, when one sits in the front half of the audience at an unamplified concert of classical music to hear that "depth of stage" is caused by the amount of added reverberation one hears around the direct sound from musicians further back on the stage compared to those in front. This is true even if the musicians in the back have greater brilliance to their direct sound, such as trumpets playing in their high register--they still sound further back.

I find that the Dutch & Dutch 8c speakers I currently use reveal more clearly than any other speakers I've owned the difference in the amount of recorded ambiance accompanying the direct sound of instruments further back on the stage. This contributes to a life-like depth of field perception, one that closely mimics what I hear live at a concert from the first few rows, even though myD&D speakers are located quite close to the wall behind them. This ambience is more "attached" to the direct sound of each instrument than with other speakers. Whether this is due to the dispersion characteristics of the speakers, their time alignment, or some other factor, I don't know.

I really think whether audiophiles prefer reflective or absorptive listening room surfaces comes down to whether they want to create a "you are there" or a "they are here" space at home. I am clearly in the "you are there" camp. To get the "you are there" feeling, you must suppress the surface reflections of your small listening room to fully reveal whatever larger venue acoustics are captured on the recording. You must suppress the "second venue" effect of your listening room's small room acoustics overlaying the concert hall acoustics captured on the recording. This demands either absorption or at least diffusion of specular reflection areas of all listening room surfaces, even those behind the listener.

I also think, however, that a great many recordings, even classical music recordings, don't contain enough recording venue ambiance to well construct a "you are there" feeling of envelopment. I think that a lot of recording engineers do this on purpose, supposing, as Toole does, that most listeners will leave their listening room surfaces untreated and that this will add space and ambience. It may well do that, but it is the wrong kind of space and ambience, a type which uniformly gets added to all recorded material and which to the astute listener just doesn't sound real in the "you are there" sense. It may contribute to a "they are here" feel, however, and some listeners may feel that's preferable, at least for some types of music other than classical. Actually, I think many listeners prefer "they are here" for most music. And without extra channels, with dry recordings many listeners may prefer the listening room's reflections to no reflections with dry recordings. That may be what is behind Toole's findings of listener preference for reflective surfaces in listening rooms.

But besides revealing the ambient cues actually on the recording (the "you are there" feeling), damping the listening room's surfaces also gets rid of obnoxious brightness from highs splashing off surfaces where the reflection time is delayed less than 10 or 20 ms. Thus, while damping some room surfaces may not improve imaging/staging much, damping them removes the excess brightness. This is especially true in small rooms like mine for the reflections from the nearest side wall.

I believe that controlling dispersion is helpful for both imaging and reducing spurious brightness. In my small room, the Dutch & Dutch 8c dispersion characteristics seem just about perfect. There is much less spurious brightness and better imaging and staging with these speakers before any room treatment is added than with any other speakers I've had in this small room. Yes, adding the absorption and diffusion makes a positive difference, but the difference is not night and day as it is with most speakers.

Some serious acoustic research, such as the Archimedes Project of the 1990s, found that thr floor reflection is the one most seriously affecting the imaging capabilities of speakers. While a heavy carpet is quite helpful in damping the floor reflection at frequencies above 2 kHz (the main band found to most affect imaging in this study), my own experiments over the decades have convinced me that with most speakers, adding a thick layer of foam absorption over the heavy carpeting can further improve imaging and staging, helping the speakers disappear as sound sources. Most audiophiles do not further treat the floor reflection, however. One simple reason is the lack of practicality. Putting foam absorption on the floor creates an obvious trip hazard in the room since the foam usually needs to be placed between the speakers and the listening seat, fairly close to the listening seat.

Someone proposed an "audiophile coffee table," one whose soft foam surface is raised from the floor by legs, avoiding the trip hazard. This is an idea worth exploring. I've never tried it.

I have a feeling, however, that such an "audiophile coffee table" will not sound as fine as putting the absorption/diffusion on the room surfaces. I've found in experiments over the years that putting bits of absorption very close to speakers just doesn't sound as good as putting more of it on the walls, floor, and ceiling. Speakers tend to sound "small," "closed down," and lack "openness" when I've placed textured or flat foam very near the back, sides, or top of speakers. I have made homemade versions of the old Watkins Echo Muffs (if you remember those) and they just don't sound the same as putting more foam at a greater distance from the drivers. Thus, I don't hold out too much hope that putting the foam atop a table will sound as fine as putting it right on the floor. But I agree it's worth a try; it would be nice to be proved wrong since this would encourage more people to treat the floor reflection with something other than just carpeting.

Primitive root diffusers won't work well at all very close to speakers since the dispersion pattern is not finely divided enough to diffuse very well at close distances from the sound source. The P.I. Audio Group Diffusers I use behind my listening seat have a denser pattern which works well at a three-foot distance and is of course just fine where I currently use them, behind the listening seat.

Textured foam like Sonex Classic (the wedge pattern) is super easy to attach to many ceilings. A staple gun is all that's needed to fire staples through the thin parts of the wedge pattern into drywall. That's the method I've used in my prior rooms. That doesn't work in my current room, however, since this room has all plaster walls and ceiling and the staples won't go into the plaster. Even finishing nails are not easy to pound into plaster. Instead, I use a combination of heavy duty velcro adhesive fasteners and duct tape to hold my 2' x 2' lightweight foam pieces up at ceiling height. The wall foam just leans against the wall without being fastened at all; the 4-inch flat foam is stiff and stable enough to do that even in 8-foot high stacks of two 2' x 4' panels.
 

KostasP.

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Hello again,

Every room suffers from and has to deal with a "split personality", caused by the Schroeder Frequency. Below it, we have bass issues; above it, we have mid \ treble issues. The higher this frequency is at, the greater the problems to deal with and smaller rooms will have a higher
Schroeder Frequency.

In your case, you can thank Mr. D&D......to a degree. Beyond that, my view is that, depending on the complexity and intensity of the spectral content of recordings and the desired SPLs, you will be constantly battling with this Schroeder "deamon"!

Cheers. Kostas.
 
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Al M.

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Hello again,

Every room suffers from and has to deal with a "split personality", caused by the Schroeder Frequency. Below it, we have bass issues; above it, we have mid \ treble issues. The higher this frequency is at, the greater the problems to deal with and smaller rooms will have a higher
Schroeder Frequency.

In your case, you can thank Mr. D&D......to a degree. Beyond that, my view is that, depending on the complexity and intensity of the spectral content of recordings and the desired SPLs, you will be constantly battling with this Schroeder "deamon"!

Cheers. Kostas.

Yes, rooms can be bitches. I know mine is. Has been a constant battle over the years. Getting better.

Rooms are among the most important audio components. Treating them properly is also one the most cost-effective upgrades one can make -- and among the most time-consuming ones. Yet time well spent.
 

tmallin

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In my room, I can listen as loud as I like on any kind of music I like without any audible problems with frequency response or room related resonances, high-frequency splash, etc. The combination of the D&D speakers' built-in frequency balance, their dispersion characteristics, the system set up and room treatment I've chosen, and judicious application of REW equalization up to 600 Hz (REW is well integrated by D&D into the 24-band parametric EQ available in the speakers; I EQ up that far to get rid of the little blip around 400 Hz that the D&D response exhibits in most published measurements and in my room) means that the sound just gets louder until the proper volume for the program material is reached, and then it just sounds jaw-droppingly, head-bobbingly great, even in my small room.
 
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KostasP.

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Small rooms can actually sound better than big ones.
Once again, a half-line addiction but, at least, this time grammatically correct! Where is your pertinently articulated response to "amplify" this view? It sounds like an insecure reaction, aligned with your addicted postings! Oh...I forgot...telephone booths sound even better.
 
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Addicted to hifi

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Once again, a half-line addiction but, at least, this time grammatically correct! Where is your pertinently articulated response to "amplify" this view? It sounds like an insecure reaction, aligned with your addicted postings! Oh...I forgot...telephone booths sound even better.
I trust your enjoying your clxs? Cheers
 

KostasP.

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I am glad that you have dealt with your room "deamons" to your satisfaction, tmallin. However, this does not negate what I said in #27. Just ask AL M. what he has gone through!
 

tmallin

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Of course this is all complicated. I will admit that I care less about exact instrumental timbre than someone like REG. I mean, I can't identify a violin manufacturer live, much less on recordings. I really don't have the background or experience to tell one brand of violin (or any other instrument for that matter) from another.

What I do know, however, is that most recordings of solo string instruments make a cello sound like a violin heard live, whereas violins on most recordings screech like no real stringed instrument. This same treble over-emphasis is common with other instruments, but seems most apparent to me in the string family. I have heard solo violins in living room concerts from less than three feet away played at full tilt in concert style and it still sounds sweet, not shrill like most recordings.

As far as halls go, sure there are terrible, good, and better seats in all halls. Trying to judge sound from a seat more than a few off center is just a recipe for disaster since it's like turning the balance control on your stereo: all the loudness relationships among the performers are distorted and that distorts the way the ensemble should sound. You really need to sit on the center aisle or within a couple of seats of center. Also, you need to sit no further away than the 13th row, preferably closer, if you want to hear any sort of appreciable depth of stage. Balcony seats can also demonstrate stage depth, but I hate looking down on instruments. Opera pits work because you don't expect sharp staging or imaging and for opera the orchestra must take a back seat to the singing on stage and the pit works to allow the singers to sing over (literally) the full orchestra going full tilt, which can't happen even if the singers on on risers with the orchestra fully revealed/exposed on stage.

People's preferences for live sound these days is being somewhat or more influenced by recordings. Some appreciate greater clarity over bass and reverb because that is what most classical recordings give you and have for decades, if not the entire period of commercial recording.

When I say I prefer "you are there" sound to "they are here" sound, I'm not really talking literally. The "there" for me is an idealized concert seat with idealized detail, clarity, reverb, and envelopment. I've had seats like that sometimes; they do exist. For me, I must have detail, depth, and reverb, but in the right proportions. I agree that live music can be disappointing in terms of sound and I would be disappointed in more than half the seats at most concerts since they are simply too far back for my tastes. I've spent most of my concertizing no further back than the tenth row and had season tickets within the first five rows for many seasons, not to mention my living room concert experiences.

For solo piano, I actually prefer NOT to hear natural bloated mono concert sound. Thus, I appreciate some unnatural left/right stereo separation in piano recordings. Even from the first row a live concert grand piano is rather boring in terms of exciting the space; it's actually better from further back since at least then you better hear the upward projection and hall ambience which adds weight and power. The old Sheffield direct-to-disc recordings of Mayorga are certainly accurate in terms of what you hear in concert, but they are boring to hear at home.

I really think that for the audio-only recordings we mostly discuss, recorded space should be at least a bit surrealized for home listening to make up for the fact that you can't actually see the musicians. This, I tell myself, is why I like recordings at home to sound fairly close up in terms of the pulled apart spatial relationships among the instruments they portray, but then wrapped in fairly rich ambience to give me that feeling of concert hall envelopment in the hall sound. Idealized "you are there" sound, as I said.

For music other than classical, there is mostly no ideal seat at a live concert since it's mostly too loud and the PA system is usually not that good. There are exceptions, of course, and I've heard some, such as at Grateful Dead "wall of sound" concerts back in the day. But generally for such music I'm content to hear "they are here" sound or whatever electronic manipulations the studio production creates in terms of envelopment, reverb, depth, imaging, staging, etc. That's why I think the Audio Circle of Confusion is such a logically strong concept and why I think it's worthwhile to short circuit the confusion if we can. I just cannot brook too much dynamic range compression and definitely cannot stand an abrasive, overly etched, gritty, high end. I stop listening mere seconds into many pop music recordings which cross that "bright" line.

The four-inch flat foam I use is remarkably absorbing, more or less like an open window from 250 Hz up. It is only in the bass frequencies where it is not equally absorbing. The basic specs for the flat foam I use are shown toward the bottom of the following web page: https://acousticalsolutions.com/product/flat-foam/
 

tmallin

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I know that there are different coefficients of absorption for different angles of incidence and positions of absorbers in the room. But I array absorption the way it sounds subjectively best to my ears, given my stated sonic goals, in a room with stereo speakers playing. I've tried different thicknesses and contours of absorbers over the years. There are huge sonic differences in my view between the 1-inch and 4-inch foam I now use, but the four-inch subjectively seems basically as good at achieving my goals as doubling up to 8 inches, so I think I've hit the sweet spot in terms of thickness. And the flat foam definitely seems more effective than contoured versions in A/B tests I've done.

One really doesn't need much absorption down into the lower midrange anyway. But leaning the foam against the walls as I do creates enough of an air gap behind the foam to render it effective enough, apparently. On the ceiling, the absorbers tend to pull away from the ceiling about an inch and are held in place by duct tape attached to velcro fasteners outboard of the foam. On the floor on top of the carpet, the carpet itself creates a bit of an air gap.

If foam worked better for this purpose truly standing in free space, something like the Echo Muffs would be unbeatable. But I've tried that type of absorption array and it is distinctly less effective at creating the desired combination of imaging/staging/lack of excess brightness than foam placed near boundaries. It could just be that thick foam out in the room is too absorbent and kills too much midrange. But foam on the walls does sound deader than diffusers on the walls and diffusers near the speakers or on the walls tend to sound just a bit too bright and image confusing to my ears with most speakers.

One bit of a compromise I have to make with foam placement in my small room and my D&D 8c speakers: the speakers' cardioid dispersion between 100 Hz and 1200 Hz requires about a foot of free space to the sides of the speaker to allow the sound to wrap around the speaker to produce the desired cancellation to the rear, or else the sound begins to get audibly colored in the lower midrange. Even foam that close produces this coloration. Thus, I have to be careful to keep the foam at least a foot from the sides of the speakers. As it turns out, that's not too hard to do even in my small room and even with speaker placement quite near the wall behind them.

No one seriously argues that recordings should reproduce the musician's perspective on his own instrument. Of course the musician hears the sound balanced differently, but what the musician hears is not the goal of sound reproduction, at least not a goal I've heard seriously espoused by anyone on either the audio engineering or consumer audio sides. Perhaps a few musicians might want to hear that, but musicians play to and for audiences and thus most musicians realize that it is the audience who should be pleased with the sound.

No, the basic problem with most violin recordings (and most recordings in general of music) is that the microphones are up high and many if not most instruments sound brighter up high since most instruments apparently project highs upward. In a former life I used to set up mikes high above the floor to mike and record church services, which involved climbing a ladder during rehearsals. Believe me, the sound up there from the instruments is quite a bit brighter than down nearer floor level. Unless the recordings are properly EQed to counterbalance the excess brightness captured by the mikes, all instruments tend to sound too bright. Experience shows that most recordings are not in fact properly EQed to correct for this basic effect; either that, or most audio engineers just prefer an unnaturally bright (to me) balance.

I know very well why audio engineers insist on high-mounting microphones. For one thing, the audio engineers want microphones to be up out of harm's way from people on stage or in the audience. But second and more importantly for "purist" microphone arrays of just two or three microphones near the front of an ensemble is the idea that putting them up high compensates through basic geometry for the fact that the instruments nearer the microphones will be too loud because they are so much nearer the microphones than the instruments toward the back of the stage.

That's true for usual microphone positions on stage or just to the rear of the conductor. But it is not true if you put the microphones back in a typical close-up audience position, just a few rows back near audience seated height, at most about 40 feet from the stage front. For a quasi-coincident array, putting the microphones near where one's ears are in "the best seat in the house" will capture more or less what one hears from there, including natural relative volume among the instruments and a natural depth perspective. That's just too simple for most engineers, though, and admittedly it's fairly impractical for live recordings. But if you can do it, all you have to watch out for is that the angle between the left and right stereo capsule exceeds the subtended angle of the musicians as viewed from the microphone array position. Of course, for best stereo reproduction of such recordings you also have to set up your speakers and listening position to approximate the same subtended angle between the stereo mike capsules at the recording.

But outside a few Water Lily and other oddball audiophile recordings, this technique is used approximately never. Thus, the almost universal need to equalize what the microphones heard to make it more like what the concertgoer would have heard, assuming the sound engineers are really interested in achieving that sort of frequency balance, which they apparently are not.

The Dutch & Dutch 8c speakers, among their many other stellar attributes, is the fact that, in my experience, they produce a more lifelike high frequency balance from a broad swath of commercial recordings, classical music and non-. That is to say, they have less apparent treble and a lot less obnoxious treble reflection problems, while still having enough treble level and certainly enough extreme high frequency extension to sound great even with the few best-balanced audiophile recordings. Until I heard them, I would not have believed how civilized yet revealing speakers could be, even in my small room, and that's even before any room treatment is added.
 

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