For public lectures, what hidden mic setup needs to be used?

Question

In "the old days" lecturers would obviously speak, sometimes to large crowds, without the advantage of modern sound systems - to wit, no microphone.

So this would obviously be still possible today (I reckon), but I still consider being mic'd up preferable (the speaker doesn't have to shout, the audience doesn't have to strain to hear).

As I will be portraying a lecturer from 1896 (Mark Twain, to be precise), I want to preserve the illusion of no mic being present, probably clipping it behind my bow tie.

I know nothing about sound systems/technology. Is this something I should purchase myself, which would then be easily used by any venue with a sound system?

What, exactly, would I need to do as to "set up"? Is it simply a matter of attaching the mic and turning it on? How is a connection made between the hidden and cordless mic and the sound system?

UPDATE

Adding on a bit, based on the comment from Rory Alsop:

So my question is, with regard to my wearing a wireless mic: would any venue with a sound system then be able to "attach" to this device? Or do they have to be a "matched pair" - IOW, are mics and sound systems "proprietary" such as software, where both the mic and the sound system need to be of the same "operating system"?

Answer 1

You will need a wireless lav mic.

Two manufacturers of such systems at entry level prices (as wireless can be very expensive) are Sennheiser and Shure (there are other manufacturers, of course).

Now, one issue is to find the way to hide the mic under your Mark Twain clothes. You might need some training, find appropriate accessories (like gaffer tape or adhesive paste). The idea is to hide the mic without generating clothes noise. Depending on your budget, certain lav mics (the mic itself, not the wireless system) are better designed for such hiding. The Sanken cos-11 and the Tram TR50 both come with nice accessories for hiding, but their price range is not low.

The second issue is the check that the place where you do the lecture (and which has a sound system) is able to plug your wireless receiver into their PA/FOH system. This you should carefully check with a designated sound person at the venue. Your receiver has quite standard audio output. It should probably be possible if you request it in advance, with maybe some adapting cables. Or at least, you will know that it is not possible.