Capturing room audio (audience questions/comments) I currently use a video camera and a Sennheiser G3 system for recording conference-type events. The G3 is attached to the speaker, and it works great.

However, there are two situations where it doesn't work so well, namely:


When someone in the audience asks a question (rooms aren't big, so they have no mic), the camera doesn't pick it up.
When we do 'round table' style discussions, there's obviously not enough G3s to go round (or record). Right now I place a lavalier mic on the table and hope for the best.


So I'm looking for advice on what is the best type of mic that would pick up sound in the room. I'm looking for a 360-degree type solution. The camera I use right now is Canon XA20 (with the handle).
Audience questions : there's not much alternative than to have another mic (probably a hand-held one) ready to be used by the audience. If the room is really small, possibly a cardioid microphone on a stand pointed toward the audience could do the job.

Round table : have one or two hand-held mics that the speakers take when they want to speak. That's a constraint on them obviously. You can also try a boundary microphone on the table.

Notice also @stib good suggestion below to have a boom operator for audience questions.