At the end of the Phase I work, we submitted a Phase II grant application, which we were not awarded. As a result, the work continued at a slower pace. Much of the mathematical background found its way into Architectural Acoustics, which was published by Elsevier in 2006. The experimental work continued in our laboratory.

The research program has recently produced impressive results. We have filed a patent application on both a recording and a playback system. The patent is now pending.