Do you regard an omnidirectional microphone on a laptop would pick up a discourse from 10-20 ft away?

And the microphone would be facing away from the fellow (I would be using the laptop to type notes...)


Answer:

If the classroom/auditorium are noiseless enough, it might be possible. But most of the time, even aficionado or AC noise are adequate to blanket the voices.



The alternative is to use an ipod (or equivalent) beside microphone and place it on the podium.
I believe so, if the person's voice is boisterous enough. What you should do to try it out, is stand 10-20 foot away and talk and see if it works.