It’s a b*tch with very little by way of a solution I am afraid. If someone knows one, please tell me, I haven’t been able to find one for the last 35 years or so LOL.
In theory a good condenser mic with cardoid or supercardoid pattern would be your best bet. Due to their far better sensitivity, you can pick up sound easier that originates further from the mic. And due to the strong directional characteristic, you shouldn’t pick up too much ambient sounds. What you can’t get rid of easily is the “space” that is obviously created by the actual distance between mic and source.
I am gonna assume that the people will be in the audience when asking the questions and thus the back of the mic will be facing the speakers and at a good distance. This will be necessary to avoid feedback.
I’d stay away from the old “default” SM58s and the like, they are way too insensitive for what you are trying to accomplish.
Since it’s wireless, you are somewhat limited to the capsule you can put on your mic. My advice would be to get a condenser capsule if you can (for Shure this would be the beta87a for example, Sennheiser has the 865 capsule if I am not mistaken and AKG the C 5, to cover the most important brands). Be ready to ride the fader though!
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