The need to “reinforce” the spoken word in classrooms, lecture halls and similar spaces at higher educational facilities is not really an option, it’s a necessity. As with any specific application, a number of major and minor factors must be considered and evaluated.
Probability the single most important factor that is usually either ignored or misunderstood is the skill inherent in the user. The vast majority of tenured or regular faculty lecturers have substantial experience in using podium/lectern microphones. They have learned over the years how to use these systems by teaching almost every day.
The problems begin with the graduate teaching assistants and other similar less-experienced presenters. Most often they don’t understand proper mic technique and are not comfortable with or even slightly afraid of the technology. This leads to poor performance no matter what hardware is employed. The infamous microphone tapping and “is this on” scenario is just the tip of the sound reinforcement problem curve.
The enormous variety of spaces in which such systems are deployed is the other core factor to be evaluated. “Classrooms” can be anything from a small conventional meeting room type space seating 30 to 50 students to a large raked seating auditorium/lecture hall accommodating 500 or more attendees.
While the basic need for intelligible speech reproduction remains, the technical problems presented and their solutions are numerous and varied. Here is a short list of issues to consider before making any hardware decisions:
1. What type of loudspeaker system (ceiling mounted /distributed) is being used in the smaller spaces?
2. Are central cluster-type array or directional column systems in place in the larger spaces?
3. Do alternative system designs include multiple directional columns distributed around the room on signal delays?
4. What type of material is being presented — does it include visuals on a screen behind or beside the lecture position?
5. Does the presenter use a pointer or other highlighting device as a part of their presentation?
6. Is the class interactive — does the presenter take questions from the students?
7. What are the general room acoustic conditions? Are there highly reflective surfaces to be considered?
Each of these issues creates its own specific