One of the goals of last summer's overhaul of Whitney Hall was to improve the acoustics of the space and increase our flexibility to support the many different types of sound the variety of artists we present produce. The needs of the highly amplified rock concert moves dance party at the end of the Blue Man Group show last weekend and the sound of the Academy of St. Martin in the Fields chamber orchestra are very different.
For classical music, the shape of the hall in conjunction with the orchestra shell is designed to do most of the work, balancing the sound in the audience and on stage for the musicians so everyone can hear clearly.
Some of the room is fixed - we can't really move the walls in the audience, and the seats are where they're going to be. But, hanging in the air and rolling on the floor we have orchestra shell pieces, and ceiling units - clouds, we call them. So the question is, how do we know exactly where to put them? How can we figure out where they will bounce the sounds the orchestra is producing?
Enter our Acoustician, Carl Giegold, of Threshold Acoustics in Chicago. Carl's been working on Whitney Hall for a while now, and he flew in this week to help us fine tune the placement of all of the orchestra shell pieces to make the Whitney sound its best. As it turns out, sound travels directionally through the air much like light, and to see where the sound will go, we can shine a light at the shell and watch its reflection. As we tilt the ceiling pieces, the distribution of the reflected sound changes, pushing more or less sound out at the audience, or back to the musicians on stage so they can hear themselves and each other as they play.
Here's what that looks like from the side of the stage, a little work light pointing up at the ceiling:
Now, check out Carl's view as he wanders around in the seating in the house:
From the audience, you can clearly see which parts of the ceiling will reflect a sound eminating from the point on stage where the light is set up to your seat. Carl explained the difference between the bands of reflected light you see - there are parts of each cloud that are wide and parts the curve up to the ceiling. The smaller highlights on the curves only reflect high frequencies, where wide, flat sections will push a clearer, fuller sound out to the audience or back to the stage. We've been staring at the ceiling making tiny adjustments to the tilt of each piece for the last couple of days, and tonight we'll finally get to hear how it all comes together with an orchestra on stage.
You probably won't see these details when you come to Whitney Hall for Joshua Bell and the Academy of St. Martin in th e Fields tonight - and really, how much looking at the ceiling do any of us do when we're listening to a concert - but hopefully you will hear them.
