Monday, July 17, 2006

Mics for in-class pickup

Wireless mics win the race. There is no re-curring setup time for wireless handheld mics in Centra-in-Class situations.

Wired mics take cables which are difficult to setup/teardown and maintain and the number of such mic needs to be much larger to cater to a reasonably sized class of 12 or more. There is no science behind the number 12 here.

Flywatters (Peizoelectric), originally suggested by some campus experts were poor in performance because of battery consumption and rapid pickup degradation on draining batteries. These would be great for Streaming/On-Demand Media but not for Centra audio. Centra audio compression kills the flyswatter sound. Handheld mics work best with Centra because of directed pickup. Omnis in general would not do well when doing Centra.

The effect of Mic Mounting In-class: desk-stand versus hand-held

In-class participants tend to position the mics for better pickup when there is NO MIC STAND ON THE DESK. Putting a mic holder on the desk is inviting pickup trouble as the in-class participant may swivel in the chair and move around. When the mic is in their hands, they would move it with them and the pickup is more consistent.

Group Dynamics: Enforcing mic usage

The in-class group in a Centr-in-Class situation does not expect to use the microphone when coming to class. So, the habit formation takes some time as they cannot imagine the frustration the distance learning undergoes as a result of missing an in-class student's comments/questions - especially when the instructor does not repeat them (too long/forgot/too short/judged trivial).

The microphones where not strongly imposed on day 1 - as a result, no one in-class indulged in this non-incentive task. The GSIs were requested to enforce mic use, by interrupting in-class students who were about to express themselves. Within 2 sessions the in-class population adapted to the mics and naturally asked for the mic in advance of making comments or asking questions. Much to the relief of everyone.

Judging from their facial expressions during inital interruptions of their verbal expression, it was clear that they didn't mind being reminded again and again to use the wireless handheld mic. Earlier, we had a situation where we did not have wireless handheld mics, but a network of desk mics. I will post about the advantages of wireless mics over wired mics & mic mounting in a different post.

Anatomy of Support Needs for a Centra-in-Class Course

Just to log the kind of support effort. A day in the life of Centra-In-Class:

Meeting With Admins, Support Requests (Exams/Ctools, General Technical Questions) 2 Hours x 6 times?. (Vic)

Production Design: Assuring mics, batteries, ordering batteries, supervising setup/teardown, sound checks, camera checks etc.

Media Assistant's time : 45 mins before & 30 mins after class.

Contingency Video Post-Processing in case of requests (this is critical in deciding whether we want to support offline viewing regularly or only in case of failure of Centra): 3hrs/lecture.

Managing/maintaining CTools site: For the course: Course admin's times + 5-6 hours eLearning Specialist's time (Vic).

Easily Predictable Costs:
eLearning Specialist: Class Duration
2 Media Assistants: Class Duration x 2
2 GSIs: Enforcing Microphone use for in-class participants.