The birth of architectural acoustics
See the related story Seen and Heard: Calderwood Hall.
I’ve been a music critic in Boston for 36 years and wouldn’t have it any other way. There may be more going on in New York; Los Angeles may have more glamour; Cleveland and Chicago have symphony orchestras of comparable quality to the Boston Symphony Orchestra; and San Francisco and even Houston have more opera. Still, I wouldn’t have it any other way. Partly because there are so many dedicated Boston musicians who play on such a consistently high level but also because at least three of Boston’s major concert venues make music such a pleasure to hear, and one of them — Symphony Hall — is widely regarded as one of the great concert halls in the world.
Acoustics is a mysterious science; maybe more mystery than science. One of our best concert halls, the midsized Jordan Hall at the New England Conservatory, underwent an expensive restoration and cleaning in 1995, and although great care was taken not to change anything acoustically, the immediate results were disastrous. The warm, intimate sound was suddenly too bright and too hot. Brasses on the stage sounded as if they were coming from behind the audience. Every turn of a page in anyone’s program book could be heard loud and clear. My joke was that I thought that the Conservatory had paid to have the notorious cement slab that had been discovered under the stage at Carnegie Hall imported to Boston.
What went wrong when there were so few changes besides new seats and fresh paint? The cause may have been the paint itself. Not as porous as the original paint on the rear walls, the new paint may have created an intractably hard surface that reflected sound without absorbing any. Within a year, the rear walls were covered with white felt, and suddenly Jordan Hall sounded more like its beautiful old self.
Opening night, in July 1994, at the elegant new Seiji Ozawa Hall at Tanglewood, there was another acoustical mishap, though one of the world’s most distinguished acousticians, Lawrence Kirkegaard, had supervised. Yo-Yo Ma was playing the world premiere of the John Williams Cello Concerto. But you could barely hear the cello! That hall had an array of movable ceiling baffles, and it took a season to figure out how to use them optimally. Again, the stage wall was covered with felt (this time red). And since then, the sound has been more than satisfactory for an open-air venue.
But Symphony Hall is another story. In this temple of art, with its traditional “shoebox” shape, its coffered ceiling and faux columns, its niches with 16 plaster casts of classical sculptures — does every fig leaf help deflect and disperse the sound? — its latticed and velvet-covered balcony railing, its wooden floors and leather seats, and its 4,800-pipe Aeolian-Skinner organ (installed in 1949 and recently restored), the sound is magical, warm, and vibrant. You can clearly hear the softest pianissimo, the most delicate pizzicato. And its current superb brass section, which for years seemed coarse and blaring, has acquired a new burnished depth along with its familiar power. Everything blooms! Everything sounds!
A conductor like Seiji Ozawa, who wanted the sections to blend into a rich undifferentiated tapestry, could get the orchestra to produce that blend. Other conductors, such as Pierre Boulez or James Levine, who like to bring out more contrast between instrumental sections and individual instruments, giving the variegated colors of the instruments more dimensionality and direction, could do that, too.
One of the innovations for which I especially admired Levine was his decision to go back to an 18th- and 19th-century seating plan, dividing the first and second violin sections antiphonally, on opposite sides of the stage, rather than keeping both sections together, which makes their differences (question and answer, call and response: true stereo) essentially inaudible. This seating plan added a new (old) spaciousness to the sonic textures. I now miss it when guest conductors revert to the previous plan, which is easier to conduct.
Symphony Hall opened on October 15, 1900. Its architects were the distinguished firm of McKim, Mead, and White, who invited a young Harvard physics professor, Wallace Clement Sabine, possibly because of some calculations he had done for Harvard’s Fogg Museum, to advise them about acoustics. His advice is now considered the first truly “scientific” approach to concert-hall acoustics: the “birth of architectural acoustics.”
Sabine seemed to have figured out what acoustician Robert Berens (who worked on the recent refurbishment of Symphony Hall) calls the “magic formula” for the effective absorption and reverberation of sound: neither too dry (for lack of reverberation) nor too echoey. As he explained it to me, the sound produced on the stage not only goes directly into the hall but also bounces off everything in sight and earshot — side and rear walls and ceiling — at minutely different times. That combination — the magic formula for absorption and reverberation — is what creates the overall hearing experience. And since Symphony Hall was one of the first major buildings to be fireproofed, Berens added, the brick and masonry reflect a lot of bass better than a frame building would.
But despite its consistent acoustical qualities, Symphony Hall doesn’t have a single monolithic sound. The experience of the music can actually be quite different in different parts of the hall. There are people who wouldn’t sit anywhere but in the back of the second balcony or close to the proscenium in the first balcony or in row W on the floor. I first started going to the BSO as the guest of an elderly friend whose longtime subscription was in Row B of the second balcony, just left of center. I was enthralled. The orchestra looked a mile away, and yet I felt swaddled by the sound. Nothing on my hi-fi ever sounded as voluptuous or brilliant.
When I first started reviewing, my press tickets were in Row M, just off the right-center aisle. I could locate where every sound was coming from, but I also felt that I was hearing more individual instruments than the full ensemble. And I couldn’t see who was playing, which made it hard to praise (or criticize) the orchestral soloists.
My choice seats now are on the side of the first balcony, fairly close to the stage. I can see who’s playing, and the sound of the orchestra seems at its most glorious, as if it’s aimed directly at me, without hurting my ears even at the highest volumes. Yet whenever I have a floor seat or a seat in the center of the balcony, I also love the fresh experience.
The only place I would not choose to sit is in the back of the orchestra section, under the overhang of the first balcony. It’s not true that there are no bad seats at Symphony Hall. These are the cheap seats that are not worth the price of admission because so much of the sound is cut off. You keep wanting to turn up the volume, but of course there’s no dial.
And while Symphony Hall is a magnificent place for an orchestra, it’s really too cavernous for chamber music, and some solo singers, even opera stars, can have a hard time being heard over an orchestra. Yet some singers can be electrifying, as when Barbara Cook ends one of her concerts singing without a microphone, and even her slightest whisper fills the hall.
Berens said he did a lot of measuring in acoustical test chambers in the process of replacing the decaying stage floor and the old leather chair cushions with softer new ones; opening the shutters of the hall’s 14 semicircular clerestory windows, which had been closed since World War II, now letting in daylight and starlight; and restoring the organ. He regards the changes we can “hear” as not only physical but also psychological. If the hall is visibly brighter, we also seem to hear a brighter sound. But he also acknowledges that with the routine maintenance of the 100-year-old stage floor, there had developed “a gross lack of uniformity. Parts of the floor were loose, parts deteriorating from aging varnish or the spit of brass players. The changes,” he says, however minimal, “are going to be perceived primarily by cellists and bassists, whose instruments make direct contact with the wooden floor.” And the greater uniformity of response across the floor means fewer “sweet spots.”
“The old floor,” BSO bassist James Orleans told me, “created a magnificent resonating chamber beneath our instruments, and one felt the floor responding as if it were a part of the aged instrument. Since the new flooring was installed, we do not get the same intensity of feedback from the floor.” Orleans says he once suggested collecting, storing, and spot-repairing the aged flooring wood to work into the new floor, rather the way violin makers incorporate old wood to make new instruments more responsive. “Evidently, that idea was not feasible,” he says. Orleans agrees with Berens that “the bassists perhaps notice the differences the floor has made more than anyone on the stage. I miss the old floor.”
Replacing the old seats also required a lot of testing. Berens’s only regret (and I’ve been noticing this problem, too) is that the half-inch of thicker padding on those hard old seats has resulted in a more precarious “tipping point,” so that more empty seats crash down during a performance when the hall is not full. Some minimal padding under the seats might be called for.
The great acoustics can actually be a problem for the musicians themselves. Another BSO player, while admiring the “glowing warmth, the resonance and extraordinary tone the hall produces, both onstage and for the audience,” also acknowledged that there was an occasional disadvantage to this very attribute. “Hearing what one’s colleagues are playing,” this player writes, “can be rather more difficult than in a slightly drier acoustic. One has to be very careful to play at the right time because other players’ note-beginnings and -endings are rendered somewhat diffuse. The lack of sharp clarity and immediacy can sometimes hurt ensemble. Naturally, the farther apart the musicians are, the more difficult the problem becomes. Any such doubt might be transformed into a lack of conviction in making an entrance.”
Musicians obviously don’t play only by looking at the conductor, though a conductor with a clear and decisive beat can help immeasurably. Most musicians will probably agree with my anonymous player that tight ensemble is not the most crucial element in all repertoire. The treasured resonance of the hall masks most of these problems anyway. I haven’t heard of a single musician who is ready to trade Symphony Hall for any other concert venue. And there’s at least one grateful listener who wouldn’t, either.
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