Ostergaard Acoustical Associates assisted Fallon Pacheco Architects and Roxbury Engineering with the design of a recording studio at Bloomfield College, part of an addition and renovation to the Creative Arts and Technology facility.
Sound Isolating Constructions: Sound isolation for the Recording Studio was the most significant concern for this project. The Recording Studio is intended to be used separately and simultaneously with its associated horizontally-adjacent Control Room, as well as simultaneously with a Multi-purpose Room located above the recording studio. Significant constructions were developed to address these concerns.
Between the Control Room and the Recording Studio, the primary separating partition is a 3-layer construction. The middle layer is CMU. Fastened to each side of the CMU are resilient isolation clips securing metal studs to the CMU while avoiding rigid connections. The partition is finished on each side with layers of gypsum board, with insulation in the cavity. Inset into this special partition construction is a large, non-operable sound-isolating window assembly, utilizing a 12-inch-deep airspace. Noise reduction through the window is excellent, measuring 50+ dB at mid-frequencies.
Between the Control Room / Recording Studio and the Multi-purpose Room above, the separating construction comprises a gypsum board ceiling supported on spring isolation hangers. This special ceiling is suspended from the concrete slab above. Ductwork and piping in the Control Room and Recording Studio are below the special ceiling construction in order to increase room volume and minimize necessary penetrations through the ceilings. Measured noise reduction through the floor/ceiling construction is superb, measuring 70+ dB at mid-frequencies.
HVAC Noise and Vibration Control: A challenging goal of NC-15 background sound levels was set for the Recording Studio and Control Room. Through the use of extremely low air speeds, selection of quiet diffusers and grilles, and the advantageous location of these rooms in the basement (far from the rooftop air handler), measurements in the finished spaces confirm that this remarkably low level of background sound is achieved. The HVAC design for these spaces also incorporates numerous silencers to control “cross-talk” through ductwork, so that the high degree of sound isolation afforded by partitions is not comprised.
Room Acoustics: Three of the four Recording Studio corners avoid 90-degree angles in plan, which promotes even distribution of reflected sound. The Recording Studio ceiling utilizes surface-mounted sound diffusers. Recording Studio walls incorporate variable acoustics panels; these expose sound-absorbent material to the room when open, but expose solid wood to the room when closed, allowing customization of the recording studio for different recording desires. The special sound-isolating ceilings in the Recording Studio and in the Control Room are finished with spray-applied sound absorption to assist with overall control of reverberation.