An anechoic chamber is a room that absorbs any echo produced by sound and prevents any form of reverb, creating a entirely static sound. The choir was recorded in this environment so that acoustical engineers can use the very basis of choral music to design concert halls and churches in the future.
"We walked in and it was like you were in a room full of cotton balls; the sound was completely shut off," said Sarah Beisser 06. "It sounded like your ears were plugged," Sara Smith 06 added. "It was like you just got off of an airplane and your ears hadnt popped yet."
The choir crowded onto rafters elevated six feet above the chamber floor, with conductor John Ferguson, organ music professor, standing on his own platform. The group sang five songs in a variety of styles from concerts earlier this year, hoping to provide good information for the scientists studying the event.
The room was designed with acoustically absorbent foam wedges that protruded from the walls. "It reminded me of egg crate material," Smith said. She then explained, "scientists can now digitally manipulate sound waves, so they can see how sounds reflect off of certain structures inside buildings. So you can manipulate the angles of the structure to get what you want."
As Ferguson explained, "The surfaces of a room reflect the sound, so you dont hear just the natural sound, you hear the version influenced by its surroundings. All the sounds we hear arent the sounds [as theyre made], theyre the sounds as they are mutated by their environment. The anechoic chamber takes away any influence that the room may have on the sound, so its just pure sound.
"There are no pure recordings without some reverb," said Doug Pierce 06. "When we first began singing, we then stopped and there wasnt an echo. You could only hear sound coming directly from someones mouth."
The unique design provided a very interesting environment for the choir. "It was a really cool experience," Smith said. "It was totally dead sound; when I came out I was deafened by regular echoes."3
Originally, the scientists wanted the St. Olaf Choir to sing, but the directors thought Cantorei would be best because they are built on unity they sing in smaller clumps of three or four members creating a more unified sound.
The absence of reverb made it especially difficult to sing in unison. "When [Ferguson] spoke it was like it was a thin tube of sound coming towards me." Beisser said. "When we were in the room I couldnt even hear singers from across the room. It was hard to keep intonation and to keep the beat. Our cutoffs werent as clear as we had hoped. It was sort of like I was singing alone."
"It was almost impossible to hear the person next to you singing," Doug Pierce 06 continued. "It was difficult to have the same sort of unity that we are used to."
Despite the inconvenience of not being able to hear the other singers around them, however, the choir performed well enough for the scientists to need only one take.
"We didnt think we did all that well," Pierce said. "But they loved it."