Culver City
TRANE MAKES “QUIET ON THE SET!” A REALITY FOR FAMOUS SOUND STAGE
TRANE’S CLIMATE CHANGER AIR HANDLER AND Q-FAN PUT THE “SILENT” BACK INTO MOVIES
Soundstage 11 in Culver City, California, has an impressive history. “Gone with the Wind” was filmed there, as was Citizen Kane, ET, City Slickers, Wag the Dog and many other famous films. But, like all sound stages in the area, Soundstage 11 also had a reputation for being historically uncomfortable. Because sensitive recording equipment could easily pick up HVAC noise, all comfort equipment had to be shut off for filming or taping. The set would be sub-cooled before shooting, but by the time a scene was over, it often was too hot for the actors and crew, and especially for sensitive equipment like computer light dimmers. Once the stage overheated, filming would halt and the whole sub-cooling process would start all over again. When Columbia TriStar TV moved into the soundstage to begin taping television shows, they made it a priority to have the HVAC system upgraded. Dale Au of the Trane-assembled design team said, “What made this a challenge was the tremendous amount of air we had to deliver to the studio. Normally, the square-footage area of a stage this size would require only about 35,000 cfm of conditioned air, but based on the studio’s requirements, and with all the stage lights on, we would have to deliver 80,000 cfm.” And of course, they would have to perform this act in complete silence.
By visiting other studios and researching their systems, the team realized they would have to shoot for a very ambitious acoustical rating of NC-18. To achieve this they decided the first thing to attack was the air handling system. The heart of the new air handling system design is two Trane Modular Climate Changer™ air handlers, each equipped with two ultra quiet Trane Model Q-fans. This fan generates less low frequency noise (the hardest to attenuate) than any other type of fan available in the industry. It was a good start. According to acoustical consultant Mark Schaffer, “(it) moves a lot of air—and it does so very quietly. It’s a real gem. Whenever I compare the Q-fan to other types of fans at the same operating point, the Q-fan is always quieter.” The air handler fan motors are equipped with variable speed frequency drives to contribute to low noise, and save considerable energy, too. Return air is drawn through an attenuating plaque built into the exterior wall of the building, making the entire building, in effect, a return air plenum. According to Schaffer the plaque forces the return air to make a turn, the equivalent of a lined elbow further attenuating the air before its return to the air handling unit.
The design goal of the system was to achieve a noise criteria rating of NC-18. According to Ken Kenyon, HVAC technician at Culver Studios, when it first ran, delivering the full 80,000 cfm it measured an even more impressive NC-17. After some minor duct-work sealing, the system has now achieved a rating of NC-15, the level equivalent to the allowable level in a high-quality recording studio. This makes Soundstage 11 the quietest soundstage in the television and film industry. With the air, conditioning system and fans operating at full capacity, the studio can still shoot a feature film. As a result, taping at Soundstage 11 means less sound editing, so the whole production goes faster and ultimately costs less money. Kenyon added, “For certain, this is the quietest soundstage owned by Sony Entertainment, the parent company of the Culver Studios. And the tenants of Soundstage 11, Columbia TriStar, are ecstatic. We used to get a lot of phone calls in our department complaining about HVAC. I still get the calls, but now it’s from people who say thank you!”
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