The key is to think about acoustics horizontally rather than vertically: to treat the entire work environment as a system and not a collection of parts.
In 1999 IFMA (the International Facility Management Association) conducted a speech privacy study (96Kb PDF) ina health care environment and compared the private offices of Constructive Solutions to regular dry wall. When matched with sound blocking ceiling tiles and a properly tuned sound masking system, Constructive Solutions met the stringent requirements for speech privacy.
Whether in an open environment or closed offices, your interiors won't puncture the acoustic envelope. It can now be maintained over the life span of the space no matter how the layout of offices and furniture changes.
Lighting not only affects your eyes it affects your acoustics.
By hanging indirect lights, rather than having direct lighting embedded in the ceiling, the ceiling tiles provide continuous sound absorption. At the same time you eliminate the reflective surfaces of the direct lighting which spread sound over a wide area.
