MIT — Barker Engineering Library

The project scope included restoration of the oculus at the top of the dome that had been shuttered since World War II, interior restoration of historic paint colors, addition of new sound-absorbing panels in dome coffers to reduce reverberation and sound-focusing, and addition of an electronic sound masking system throughout the Barker Engineering Library reading room located in the rotunda below the dome.

Acentech made extensive acoustical measurements on site, of background noise levels and reverberation.  Acentech used that information to advise the project team regarding acoustical finishes, potential upgrades to HVAC, and installation of a sound masking system. Acentech then created a 3DListening (3DL) simulation of the space, and presented to MIT Library and Facilities staff and to Shawmut Construction the acoustical simulation in our office, which included a demonstration of the effectiveness of electronic sound masking, and the relative effectiveness of various approaches to sound-absorbing finishes in the room. In the end, an electronic sound masking system was installed according to Acentech’s design and specifications, and new sound-absorbing finishes were located in the coffers of the dome ceiling that mitigate the sound-focusing effects of the dome’s shape.

Acentech also programmed and designed a portable audiovisual system to support events and functions held in the reading room which was designed for rapid setup and teardown. The loudspeakers are designed to provide optimum intelligibility using digital signal processing and a vertical array of loudspeaker transducers.

Acentech was honored to be chosen to contribute to one of the Commonwealth’s most historic and iconic buildings. The oculus that was restored as part of the project opened up the skylight to allow light to come through for the first time in 70 years.