In the perimeter studios, measured noise level from the street was a serious issue as they were well above acceptable criteria. To achieve the appropriate interior levels we recommended the windows be treated with a secondary glazing of heavy laminated glass, along with extra requirements for wall constructions.
In the interior studios, the main noise issue was the substantial HVAC ductwork above the ceiling. In order to eliminate excess rumble noise from interrupting recordings in these studios, we specified a sound barrier ceiling. The benefit of this construction was twofold, in that it protected against HVAC noise and prevented noise transmission from activity from the floor above.
In both the interior and perimeter studios we recognized that there was some exposure to subway noise and vibration. We measured the noise and vibration from the subway prior to the building construction to assess its potential impact. Based on our analysis, we determined that the subway noise would only be audible in spaces with low noise criteria of less than NC30. In order to maintain the quiet environment required for a studio, we designed a room-within-a-room construction for the studios on the 8th floor. This floating floor construction involved pouring a four inch thick concrete floor over spring isolators.