The planning for the renovation of the 280 seat Wesbrook 100 lecture theatre began in the summer of 1996, with construction slated for summer of 1997. The intent was to develop Wesbrook 100 into a 325 seat lecture theatre that would be suitable for the Sciences faculty plus outside rentals and seminars, utilizing modern video display systems, an improved audio system and a simplifed control system using a touch screen. Working with Hotson Bakker Architects, we began work on room acoustics and the A/V system design. In July of '96, the provincial government froze all construction funding and the project was halted until April of 1997. The project was reactivated with the construction date set for May 97, which meant that a comfortable design time frame was compressed into a fast track design and construction schedule. We worked closely with the architect to maintain the design and construction schedule.

The original room configuration had problems with excess HVAC noise and excessively long reverb time which resulted in poor speech intelligibility, and difficulty for the students communicating across the room. The HVAC noise control design was done by BKL Consultants, and we developed the design for both the acoustical treatment and the A/V system design. The HVAC noise was reduced by 20dB to bring it in line with backgound noise criteria for classrooms. The acoustical treatment reduced the reverb time significantly to improve the speech intelligibility of unamplified speech, as well as reinforced speech. The measured %ALCONS was a very low 3.3% (STI 0.74), indicating very good speech performance, especially critical for listeners with English as a second language. Here are the before and after reverb time values for the unoccupied room...

The A/V system went through several evolutionary changes through the design process. We arranged video source and video projector demonstrations for the faculty so that they could make objective decisions based on the cost versus performance trade-offs. Through this process, the faculty decided to upgrade from a single chip CCD document camera to a three chip CCD device, and from a 750 ANSI Lumen projector to a 2500 ANSI Lumen light cannon, mounted in the projection booth at the rear of the room. The front screen projection configuration requires the use of very high brightness video projectors to allow an image to be viewed with partial room lighting suitable for note taking. The system can display 1024x768 pixel computer images, video tape sources and the document camera. There are two tiltable 10'x10' screens at the front to allow either screen to be used with an overhead projector, or with projected video or slide images, or any combination of the two. As well, a large electric drop down screen is in place to allow a single large image to be projected from the projection booth in the rear of the room.

The ceiling height is just over 7 feet at the back of the room, and only 15 feet at the front of the room, which resulted in a substantial variation in sound level with the 60 foot deep room and the original column speakers. The new sound system was changed to a distributed ceiling speaker system using digital signal delays and high quality 6.5" loudspeaker devices. A pair of image speakers flank the projection screens, and the ceiling speakers are delayed to give the image speakers precedence for A/V playback. The sound system is quite transparent in its speech reinforcement, with the signal delays making the instructor the apparent source of the speech.

The lectern contains an electric scissor lift for the copystand to keep it safe from vandalism and theft. There is a PC and a Mac presentation computer with the display switched through a single 15" monitor to minimize the space consumed in the lectern, and the computers are connected to the UBC network to allow lesson materials to be displayed directly from a web browser. There is a VCR and an auxillary video input at the lectern as well.

The initial project was done while we worked for BKL Consultants between 1991 and 1997.