Restating the obvious: Finnish study finds that shoebox halls sound best
mainResearch at Aalto University in Finland confirms that music has a wider dynamic range in rectangular concert halls of shoebox shape. ‘Our research is the first that explains how halls influence perception of dynamic expression,’ says Dr. Jukka Pätynen.
Oh, really? Read here.
We’ve known for two centuries that shoebox works best. The issue is how to make other, more flexible halls work better.
Having known for decades that the shoebox shape works, I am always astonished that architects continue to ‘experiment’ with different shapes. Hong Kong’s 1989 Concert Hall is an oval with a kink! As audiences and musicians are aware, the architect who thought that up sadly had little knowledge of music. Yet, surely there has to be some correlation between width, length and height? If not, how is it that Avery Fisher Hall remains less than satisfactory after how many refurbishments – and yet another $1 billion + about to be spent in another attempt to get it right?
“The issue is how to make other, more flexible halls work better.”
There is no guaranteed way to do that except by using electronics. In the old times there was a solution to bad acoustics though – burn the whole thing down and build a new hall instead. How many times did the King’s Theatre in London burn down? The shoebox is the best shape for non-amplified music (classical or otherwise), so maybe it’s time to take that as a starting point for any new hall design in the future.
We knew for centuries that the earth orbits the sun. It just did. But how? Newton then came up with an explanation: the theory of gravity. The discovery of gravity did not stop the earth from rotating around the sun…
Classical research on room acoustics is heavily based on the assumption that acoustics is linear. That is, the sound is influenced always in the same way, independent of the type of the sound, be it a human voice, gunshot, or during a tutti crescendo from a large symphony orchestra.
Many scientific studies relying on various subjective sources have concluded that the old shoebox-style concert halls are often preferred over many alternative, more modern designs. They tend to have higher values measured on standardized parameters (strength, lateral energy, reverberation time, etc.) – which are once again thought not to depend on the original sound. They just modify the sound in a certain way. However, the article establishes a direct connection between the acoustics of the hall and the dynamic expressivity in music. This dynamic responsiveness explains how the shape of the hall relates to the hall “living” with the dynamics in the performed music. The halls with higher responsiveness happen to be the shoebox halls.
If the current problem in acoustic design is how to make other, more flexible halls work better, shouldn’t the study in question take us a step further in the right direction?
Well done, Jukka!
And, btw, even if this was just restating the obvious, it would have its merits though. Some things can’t be said often enough.
Btw 2: Just having a shoebox isn’t a guarantee for good acoustics either, cf. Alte Oper Frankfurt.
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“Simon S.” used to comment as “Simon” on Slipped Disc. He has recently changed his nick name to avoid confusion.
My own theory about non-shoebox attempts is that they are wanting to get the audience closer to the stage for a more engaging experience. If you sit in the back half of a shoebox hall you might as well be listening on a nice radio for all you’re going to be able to observe about the performers.
What’s the point of observing a solo singer or pianist from the side or from behind, when you barely can hear him or her?
No one is forced to – it is their choice. In case of pianists, it sometimes works relatively well.
And sometimes it is an advantage to see a soloist exclusively from the back.
There’s that, certainly.
But there are also more than a few architects who simply cannot bear to design something the same way it has been designed for centuries.
In reading about the Philharmonie in Berlin from another post, it seems that is not a shoebox hall and yet is regarded as having fine acoustics.
What’s the story there?
the story there is, that it doesn’t have a particularly nice acoustics for most of the seats, but a very nice resident orchestra. The acoustician who was responsible, Cremer, was very upset, that his warnings were ignored and his plans overruled for visual reasons.
Commentary by Brian McCreath of WGBH on the Philharmonie acoustics:
http://www.wgbh.org/articles/The-Berlin-Philharmonic-2852
“…When Hans Scharoun’s modernist masterpiece first opened, replacing after many years a hall destroyed in World War II (left), the Philharmonie was, if not an acoustical disaster, at least a great disappointment. But in a rare instance of a bad-to-mediocre hall being transformed into an absolutely superb one, modifications were made over the years to create one of the great concert halls of the world…”
That article is dead on in every respect, form the description of the nature and quality of the sound to the “feel” of the architecture. The sound in the Philharmonie is very clear and even, or “true” as the author puts it, which means in most areas of the hall, you can hear very clearly what is going on on stage. The sound travels very freely through the room so it’s a fairly direct, immersive sonic experience on most seats except maybe those at the very top of the hall. Plus you can see very well from most seats, too. All this complements the playing of the BP very well and it supports their highly involved, edge-of-the-seat style of playing. They are right in the middle of everything (more or less literally), and you as the listener are right there, too, not on some floor level below the stage with the orchestra far away and above you somewhere.
What is different about the hall acoustically from many others is that it has that crystal-clear, “brutally honest” sound. Which means it has not much of that nice warm, rounded-off edges quality that many of the classic shoebox halls have (at least the good ones). It does not add the kind of warm “aura” to the sound like the halls in Vienna or Boston. And it is also remarkable in that you can hear yourself very well on stage even if you play in a big orchestra. At the same time, you can hear everybody else on stage, too. But the degree to which you can hear yourself comes as a little bit of a shock to many when they play there the fist time because you feel a little “naked”.
The tweaks that were tried out in the years after the opening was to first raise the stage which was actually lower than it is today, and add some of the acoustic “clouds” above the orchestra which help deflect some of the sound which it was felt was lost under the high ceiling.
But what turned out the be the decisive modification which helped the hall found its acoustic “personality” was discovered more or less by accident: the amphitheater like shape of the stage surface, rising up in semicircular steps around the front center of the stage. The original stage was much flatter and lower. The rising steps were installed, at first temporarily, for one of Karajan’s film productions, at some point in the later 60s or early 70s, not for acoustical reasons but so that it was easier to see and film the whole orchestra. It was then discovered that it significantly improved the projection of the sound into the hall, so they installed a permanent podium with semi-circular modules that can be individually raised and lowered to various levels. That did the trick.
Re the “rising steps”
Easier to see and and film the orchestra: yes
Better projection of sound into the hall: not really
Who told you that?
And your claim of clarity is in vane, if you think about the over 50% of seats, where you have a mediocre or even very bad projection of the sound from soloists like singers, cellists, pianos, etc.
Basically any instrument that radiates sound directionally leaves a majority of listeners at a disadvantage.
That problem is much less so in “shoebox” layouts.
Already the old Greeks knew, that you build a wall behind the stage for acoustic reasons for any artistic performance of music and theatre.
Arenas with audience all around the stage were considered suitable only for circus games and horse races…
Better projection of sound into the hall: not really
Why not?
You are avoiding the question. But let me answer nevertheless.
“Better projection of sound into the hall” is unprecise blurry and irrelevant terminology. As if “sound” and “the hall” were singular instances. In reality – and even more so in arena layouts than in shoebox layouts – many sources/instruments are projected very differently, depending on factors like position of source, position of listener, early reflection pattern that is created by the hall in particular relation these two positions, directionality of the source, etc.
In arenas like Berlin Phil the sound of the orchestra, balance, timbre, reflection pattern etc. Fluctuates highly depending on where you sit. Add to that the slap echoes from surfaces you have at many seats, and “sound in the hall” loses its sense as a singular entity. Almost every seat sounds different. That effect ist less pronounced in shoebox designs.
Typical for arenas like Berlin Phil is that only a minority of seats have satisfactory acoustics, while in shoebox designs usually a much higher percentage of the seats are good seats acoustically.
Anonymus says:
Re the “rising steps”
Easier to see and and film the orchestra: yes
Better projection of sound into the hall: not really
Who told you that?
Somebody who was there. I will tell you who it was when you tell us who you are. It’s also mentioned in a book about the Philharmonie. I will tell you the title of the book when you tell us who you are.
I would like to bring this writing into attention – it seems to communicate most of the key points in our study in a clear manner:
http://www.fastcodesign.com/3027099/why-your-stodgy-old-concert-hall-looks-the-way-it-does
Jukka P’s explanation is clear, non-technical and persuasive. Good job.
That seems to totally make sense since it is a well known fact that with most instruments, when they play louder, the level of the fundamental note doesn’t actually vary that much, but typically, the louder the instrument is played, the stronger its overtones get (which is why many instruments also sound much brighter when played louder, especially brass instruments – most of that bright brassy shimmer is strong overtones).
So it would make sense that a hall which supports transporting these overtones effectively will appear to the listener to be much more “dynamic” than one which doesn’t.
It also seems to make sense that a hall in which those overtones are very effectively transported to the listener and reinforced by reflections coming primarily from the directions in which the listener’s ears are “pointed” would have that quality. But it is really a given that the shoebox shape, while the listener’s ears are indeed “pointed” at the side walls (more or less), actually achieves that most effectively? After all, the angle of incident of the first waves coming from the stage *to* the side walls is quite steep in the middle and the back of the hall. Doesn’t that suggest that the relative “dynamic” effect is significantly rolled off towards the middle and the back of the hall?
And then it seems that most shoebox halls – I am talking about the successful ones, like Vienna, Amsterdam, Boston – are actually more known for their warm, rounded-off sound quality which is the result of smoothly rolling off overtones which to me appears to be the opposite effect of what one would expect, based on this explanation model. There are just as many terrible and very “undynamic” shoebox halls as there are effective ones.
Of course, saying that “the angle of incident of the first waves coming from the stage *to* the side walls is quite *steep* in the middle and the back of the hall” doesn’t make all that much sense. I should have said “…is quite *shallow* in the middle and the back of the hall”. Wrong choice of words. But I think it is reasonably clear what I mean.
As far as I know, shoebox halls are more known for their favorable characteristics for such acoustical parameters like strength, laterality of diffuse sound, and a good compromise between blend and clarity.
Strength is why the old Greeks built a wall behind the stage…
Of course an orchestra like the Berlin Phil is able to play strong nevertheless, consisting of so many of the best individual musicians of this planet and also playing very fine instruments that can play really loud if necessary.
The old Greeks didn’t build shoebox shaped roofed concert halls with flat floors, they built open air amphitheaters with rising, semi-circular seating areas. The Philharmonie is actually closer to, and the design was in part inspired by, that kind of venue, rather than the classic shoebox shape (as is pretty obvious I think when you look at the hall).
Of course an orchestra like the Berlin Phil is able to play strong nevertheless, consisting of so many of the best individual musicians of this planet and also playing very fine instruments that can play really loud if necessary.
That doesn’t really have all that much to do with them having better instruments. The instruments they have aren’t generally all that much better than what most other professional orchestras have. I have heard dozens of other orchestras in the hall, too, and they generally didn’t have a hard time projecting their sound and filling the hall sonically. But you can hear the difference in sound between those orchestras very well because the acoustics are so “brutally honest” clear.
Shoebox is not synonymous for flat floor. Maybe it’s a misnomer. Take an excellent acoustic like the Dvorak hall in Prague, with a rising floor for the audience. The essential features of the “shoebox” are not flat floors, but strong lateral diffuse reflections (which are psychoacoustically preferable over refele tions in the vertical plane), stage walls that direct the reflected sound toward the audience, resulting in better overall strength; and last but not least a stage at one side where directional sound sources like many instruments and singers can cover a major part of the audience with strong direct sound with good timbre.
Have you ever been sitting in a circus arena like the Berlin Philharmonie on the sides or even the back of the orchestra and hearing – or actually not hearing – singers or soloists that are facing away from you? It’s actually really absurd, but so was the size of Karajan’s narcissism.
Another non-shoebox hall with excellent acoustics is Disney in Los Angeles. I understand this was a goal for the design and not merely a coincidence.
Also, what is the effect of putting the performers halfway down the long side instead of at the end.
A lot of musicians would strongly disagree with you about Disney (i’ve talked to a number of them both inside and out of the LA Philharmonic). It’s an acoustically precise but insufferably cold space, with absolutely no bloom to the sound — and even worse, the hall actually forces the brass to work harder to get their sound out. It also makes the strings sound brittle as hell. A great music director might eventually help the orchestra find a way around that, but right now I think the hall is incredibly limited in that respect. You can hear a gum wrapper being unwrapped in the terrace, but if the orchestra tries to get some power, you can practically see Yasuhisa Toyota come running in from the wings with pillows and stuff them into the bells of the brass players’ instruments.
You say that like it’s a bad thing …
because it is.
Nice one, MWnyc!
How could I resist?
That fits my own impressions of Disney perfectly, the “pillows in bells” is exactly what I mean by “there is a lid on the sound”. The brittleness of the strings you mentioned is an effect of the uneven distribution from lows to highs. I the reason for all this and that you can also hear very soft sounds like a gum wrapper far away is that the hall is quite deep, valley like.
No “bloom” in the sound?! What? I assume you’re referring to resonance or reverberation. If so, Disney Hall has an intrinsic “bloom” that becomes startling more apparent when assessing the acoustics of performances there compared with those in other settings. My theory is that the great clarity of sound in WDCH gives a person the corresponding first impression (a misleading one, at that) that there isn’t much of an appealing echo-y quality around that sound.
“Great clarity” can mean the compromise between blend and clarity has been offset toward the side of clarity, which means there is less blend and envelopment, unless you know how to unify both parameters…
If you – Desdom – speak from the Toyota camp, apparently you do, you might have missed the key question of lateral reflections, which enable the acoustic designer to achieve greater blend and clarity simultaneously. All Toyota designs show a negligence toward the importance of lateral reflections.
People with acoustical expertise who have spoken with Toyota are shocked how apparently clueless the man is about psychoacoustic science, particularly the decisive perceptive differences between lateral and vertical sound incidence.
You can’t design a circus arena and bring the reflections you can’t create from the sides, due to the unsuitable architecture, now from the ceiling or the back of the listener. Nam qui fact…
Disney *is* a shoebox; the fact that you think that it is not is a tribute to Frank Gehry’s genius at “wrapping” the building with those swooping panels. The hall was originally designed along the lines of the Berlin Philharmonie, but the LA Phil’s acoustic firm (Nagata and Assoc.) refused to sign off. (Gehry tried to get Nagata and Cremer to have dinner together, but they would not talk acoustic theory to each other!) Flexibility was also ruled out in the design process for ideological reasons, which has left the hall with a substandard amplification system ever since.
I give a talk on Disney Hall where I superimpose the floor plan of the auditorium onto the Amsterdam Concertgebouw: it fits perfectly, even to the seats behind the orchestra.
Toyota doesn’t talk acoustic theory to anyone, because he knows nothing about it. He is a charlatan.
Cremer doesn’t talk acoustic theory anyone anymore, because he is dead… since 1990…
But then in Hollywood anything is possible. 😉
Apparently the main design of WDCH was done in the late 80s, so it is possible that Cremer was involved in it, or at least consulted before he died.
Yes – the acoustic design process and negotiation took place in 1988-89. The Nagata-Cremer meeting, which was earlier (1987, in Europe, right after Gehry got the gig) The Getty has extensive documentation of all aspects of the design and construction of Disney Hall, including the acoustic design process.
Now that’s very interesting that it was still mainly designed by Nagata, because that puts the number of halls Nagata’s pupil Toyota designed himself – that are good – at zero. Disney is arguably a decent hall, but nothing after that anymore Mr. T. was involved with can be described as worth the effort and the expense.
And the next acoustical disaster made by Mr. Toyota, the new Philharmonie in Hamburg, which is currently under construction, is waiting to happen soon. Mark my words.
The most overrated acoustician was Russell Johnson, who puzzling enough was used in the commissions of so many concert halls in the US and, less so, Europe. His prime notorious work, of course, and sort of an ill-fated topper of his lifetime of projects, was Verizon Hall in Philadelphia’s Kimmel Center.
The fact Johnson treated the ceilings of his concert halls, which are so crucial to fostering good acoustics, as sort of an afterthought, by often making them far too high and too lofty, and in some of his major commissions adorned with silly movable dashboard-looking whatchamacallits, suggested he was the epitome of a charlatan.
Even though his hall in Dallas (Meyerson) was judged as having good acoustics, the two times I experienced concerts performed there left me scratching my head, as I wondered “this is supposed to be exemplary sound?!”
If you had the courage to put a name to your convictions, they might be respected. As facts stand, Russ Johnson is responsible for the best modern hall in Britain (Birmingham) and the best in continental Europe (Lucerne). These perceptions are incontrovertible. NL
Ah yes, Verizon Hall in Philadelphia. It really was an ill-fated capstone to Johnson’s career – emphasis on the fate. Particularly since the hall didn’t even start to approach Johnson’s design until nearly two years after it opened.
The critics who came from all over for the opening concerts and found Verizon Hall to be an “acoustical Sahara” were listening to music in a construction site, not a finished concert venue. Johnson’s trademark resonating chambers with adjustable doors were all filled with construction supplies. During the performance, the air conditioning went on at full blast (this was mid-December, no less), and no one could work out how to turn it off.
(The opening of the Perelman Theater, the Kimmel Center’s chamber music venue, the following evening was just about as bad: the musicians had had to rehearse through last-minute construction work (which wasn’t complete by curtain time, either) and the guest soloists – Sylvia McNair, Eugenia Zukerman, and Leila Josefowicz – were so fed up that, for their encore, they put on hard hats and did “Everything’s Coming Up Roses”, Broadway’s great anthem of pathological denial.)
As for Verizon Hall’s resonating chambers – well, they’re in the walls of the upper tiers, which means that people sitting up there can see into them. The Kimmel Center’s chairman, developer Willard G. Rouse, was appalled that audience members would be able to see the chambers’ bare interior surfaces; he insisted that curtains be hung in there to hide the walls, the effect on the acoustics be damned. The curtains did not come down until Rouse died – and when he did, not only did Kimmel staff take the curtains down, they went out of their way to tell The Philadelphia Inquirer about it.
And today? Well, the acoustics aren’t as great as everyone had hoped, and maybe they’re not as good as in Birmingham or Lucerne or Dallas. But they are definitely not terrible, and they’re certainly better than the orchestra’s former venue, the handsome old Academy of Music, which was built as an opera house and works well for that purpose but doesn’t sound so good when the orchestra in onstage instead of in the pit.
Mr Lebrecht, while Symphony Hall in Birmingham may be the best-sounding concert venue in Britain in some circles, another hall in your country, St David’s Hall in Cardiff, Wales, has been rated even higher in a few surveys done by an acoustician who’s as well known as Russell Johnson. I’m referring to Leo Berenek.
By the way, if you think I was being too harsh towards Johnson, Berenek’s answer to Johnson’s major dud of Verizon Hall was the work that Berenek did on the truly notorious Philharmonic Hall in New York City in the early 1960s, now known as Avery Fisher. That project was infamous for its use of gimmicky and ultimately worthless “surfboards,” or surfboard-shaped objects hung on the hall’s ceiling in the naive — and apparently non-scientifiic — belief they would help enhance and disperse sound.
Just about every major acoustician over the past 50 years, including Cyril Harris (who redid the New York Philharmonic’s home in the 1970s and, among others, is also responsible for the acoustics in the major concert halls in Minneapolis and Seattle), has come up with his share of clunkers, and surprising ones at that. That’s why the field of acoustician may rightly trigger skepticism among insiders far and wide, and even elicit shouts of “charlatan!”
I’ve heard both. St David’s not great.
As is true of so many things in life, a person’s impressions of what makes something good, average or poor are subjective. One of the quote lines in this article I came across several years ago is an illustration of that:
http://www.theatlantic.com/past/docs/issues/96jun/tangle/tangle.htm
“The music critic for the Boston Evening Transcript was not impressed, however: after the inaugural concert [at Boston Symphony Hall] he wrote that “the tone was beautifully smooth . . . but it had no life, there was nothing commanding and compelling about it.” “
@ Desdom: “…Just about every major acoustician over the past 50 years … has come up with his share of clunkers, and surprising ones at that. That’s why the field of acoustician may rightly trigger skepticism among insiders far and wide, and even elicit shouts of “charlatan!”
True, but while some acousticians produce the occasional clunker, others are more consistent in creating them. One of these would be Mr. Toyota these days. Psychoacoustic properties of lateral vs vertical sound incidence are apparently unknown to him.
Or listen when he talks about resonating orchestra podiums. He says, he has invented the acoustical perpetuum mobile, no less. He claims his podium construction can resonate in a way that more sound energy is emitted than being entered into this podium by sound propagation through air and solid contact of instruments on the podium.
You tell him the – easily demonstrable – fact, that a double bass has more strength and resonance standing on a solid heavy floor than on one of his “magic” moveable podiums, and he will say it is not so.
It is bewildering and the concert halls that are clunkers and the subsequent damage to the public hands who finance them goes into the billions by now. In his case the title “charlatan” is well deserved.
I can kind of see that when it comes to the two sections of audience behind the podium, on either side of the the organ, although those sections are much bigger in the Concertgebouw than in Disney. But there are large sections on either side of the orchestra which the Concertgebouw simply doesn’t have. Also the relative dimensions are quite different, with the main floor of the Concertgebouw just a big rectangular (almost square area). I guess one can make them fit somewhat (but perfectly?) by applying distortion to account for the flat vs. deeply curved floor plans. But I sincerely hope that that is not how Gehry arrived at the shape of the inside of the hall. That would be totally nonsensical, maybe a clever desing trick, but thing s don’t work out like that as they do on paper, as we know from so many screwed up concert halls which look fancy but sound crappy.
Gehry tried to get Nagata and Cremer to have dinner together, but they would not talk acoustic theory to each other!
Probably not a loss since Cremer didn’t get the Philharmonie right anyway. It took years of experimenting to get the hall to sound right. What acousticians sell is mostly vaporware anyway.
Berlin Philharmonie still is far from very good acoustics. Let’s be honest. Too much damage has been done to the world of newly built concert halls by the major misperception that a great orchestra like Berlin Phil means it must happen in great acoustics. Not so necessarily.
AFAIK Cremer was forced to work around the decision of an architect and an egomaniac chief conductor, and he was overruled in the major design decisions in favor of a design that puts Karajan in the middle of everything. He then tried to make the best out of an acoustical concept that was already compromised on paper and he knew it and he complained about it, yet not publicly, since that was not possible within the usual contracts.
The acoustics in WDH aren’t all that great, certainly not as good as the hype would suggest. It is a quite spectacular and, I think, attractive building, a nice space to be in, and certainly not a bad hall. But it is very unbalanced, with a rich, almost boomy low end, it carries well in the mids, but the high end is quite muffled and hall overloads very easily when you have a big orchestra playing at high dynamic levels. The sound almost seems to “max out” at some level, as if there was a lid on it.
Of course, it is much better than the previous hall (Dorothy Chandler Pavilion) but that in itself doesn’t say much; that hall was really terrible, totally dry and dead.
My impressions, exactly. Disney Hall could stand to have more warmth to the sound, a less aggressive, almost boomy bass response, and the swallowing of loud tutti sounds in the orchestra. I haven’t totally enjoyed one performance in WDH in all these years. Also, it is a terrible venue to record the Philharmonic, lacking for firm imaging of the sound, which sounds as if it is floating and unstable.
There are certainly great shoebox halls – Musikverein, Concertgebouw, Boston’s Symphony Hall, Seattle’s Benaroya Hall (perhaps not quite in the same league but quite nice). But a shoebox is neither necessary nor sufficient: There are mediocre shoebox halls like Alte Oper or Fisher. And a number of lovely non-shoebox: Carnegie, Disney, Vienna’s Konzerthaus (I liked it, anyway), Vancouver’s Orpheum (and similar renovated old movie theaters), Moscow Conservatory.
One of the downsides of shoebox halls is that many seats have lousy views. Symphony Hall and the Musikverein are two good examples.
From the players’ point of view, knowing most of the above mentioned halls by experience, would like to mention one particular (non-shoebox) hall I mostly liked, the Symphony Hall in Osaka, Japan.
actually Osaka is very much in the “shoebox” range, as we can see from this picture, stage in front, majority of audience in front of the stage.
http://www.ieij.or.jp/english/what/pg_09.html
What’s people’s views on Symphony Hall Birmingham? This hall is based on the shoe-box design and i don’t think anyone has ever criticised it… I for one was very impressed when with the acoustic when i visited in the 90’s. And wish we had a hall of similar quality in London….
Other very good and recently built shoebox concert halls:
Birmingham
Luzern
Stavanger
…
It is a positive surprise that the article inspires to such an active discussion on room acoustics in particular concert halls.
Michael Schaffer was wondering about the results where the responsiveness is increased when moving further away from the stage. Here, the directivity of the sources should be considered in combination with the varying reflection angles. Of individual instruments, the trumpet and trombone are probably the most straightforward examples of a directivity patterns that become narrower with higher frequencies. The sources (loudspeakers) utilized in our measurements function pretty much the same way. In a rectangular hall, when listening the orchestra quite close to the stage, the first lateral reflections arrive from a wide angles at the sides. Considering the directivity of the instruments that exhibit the highest increase of harmonics at high dynamics (e.g. brass section), the high frequencies are not radiated much to the point from where the first reflections are coming. Instead, when moving further away, the angle becomes shallower, as pointed out by Mr. Schaffer. Then, more of the high frequencies can “fit” into the paths of the early lateral reflections reaching the listener. At the same time, the early reflections become stronger in relation to the level of the direct sound. The latter aspect is, however, compensated for in the published article’s formulations.
With regard to the diffuseness of the early reflections, quite recent publication by our research group has shown that, combined with the direct sound, diffuse reflections tend to scrable the temporal envelope of harmonic signals. This weakens the coherence of the harmonics, and therefore partially break down the so called precedence effect. In practice, this means that early reflections from diffuse surfaces do not integrate so well with the direct sound in our brains. In contrast, when the reflections are from flat walls, our brains integrate them better with the direct sound and the result is more powerful total sound with high clarity. Moreover, if such reflections are coming from the side (lateral reflections) they color less the sound than reflections coming from the ceiling or from the back wall of the stage.
A demonstration video can be downloaded from: http://scitation.aip.org/docserver/fulltext/asa/journal/jasa/129/6/1.3579145.original.v1.mp4
The actual article discussing the reflection types can be read here: http://scitation.aip.org/content/asa/journal/jasa/129/6/10.1121/1.3579145
If we take a look on some photos of empty Musikverein, Concertgebouw, and Boston Symphony hall, the lower side walls are in fact nearly flat. Yes, there are some statues and pillars, but for the most part, the walls provide a specular, wideband early reflection. In the higher parts of the halls there are various amounts of diffusing surfaces are in effect for longer sound paths. That is, late reverberation.
Another point worth considering is the raking of the audience area. In the classical flat-floor shoebox halls the stall seats provide a view only to the first couple of rows in the orchestra. On the other hand, looking from the center of the stage, the audience covers much less area from the spherical surface where the sound is radiating from the orchesra. In some modern designs, such as the Walt Disney hall already discussed here, the audience immediately “consumes” a considerable part of the sound. It is good to remember that the orchestra can only produce a limited amount of sound. For the end of this comment, have a look at the Music Centre hall here in Helsinki: http://tinyurl.com/MusicCentrePic .
“With regard to the diffuseness of the early reflections, quite recent publication by our research group has shown that, combined with the direct sound, diffuse reflections tend to scrable the temporal envelope of harmonic signals. …, this means that early reflections from diffuse surfaces do not integrate so well with the direct sound in our brains. In contrast, when the reflections are from flat walls, our brains integrate them better with the direct sound and the result is more powerful total sound with high clarity.”
Important to note, that for such reflections to be beneficial, they have to arrive within a certain time window, not too early (coloration of sound) and not too late (annoying echoes). For average music signals that time window is roughly between 20 to 50 ms. For very percussive sounds, already at about 30 ms echo effects start to become audible.
Pete Parker wrote: “What’s people’s views on Symphony Hall Birmingham? This hall is based on the shoe-box design and i don’t think anyone has ever criticised it… I for one was very impressed when with the acoustic when i visited in the 90′s.”
I dislike it myself because the reverberation comes from behind the stage and does not surround the listener as it does in a good hall: one has no impression of being IN an acoustic. It is approved of, perhaps, as a consequence of the fact that the primary experience of music for most people is based on two loudspeakers at the other end of their living room on recordings made so that the reverberation is located behind the direct sound. This was what I heard in Birmingham, and to a slightly lesser extent in Dallas, and I felt cheated.
Nobody is commenting upon another element of modern concert halls: most of them are very ugly and characterless. The old halls – at least, the best of them – have ornamentation which contributes to the musical experience, also visually creating a space removed from everyday life. Modern concert halls merely stress everyday, contemporary life as we knew it before entering the hall.
It seems that possessing more factual scientific information in acoustical matters does not necessarily translates into ability to produce superior acoustical results. Otherwise most contemporary luthiers everywhere would have been able to create string instruments of far better quality than those made three centuries ago in Cremona. However this does not happen. That is why I do not believe that people who “know more” about acoustics are necessarily the ones that I would trust with building the next great concert hall. And, by the way, those who think that WDCH is shaped like a shoebox probably own some of the world’s funniest-looking shoes.