Karyn
I don't have any ultrasonic transducers in my gig bag... Will an SM58 do?
Your gear list contains a Studio 192. Assuming you ever use 192 or even "just" 96 kHz sampling rates, you have also to believe that it is worth caring about signal in the 40 kHz region too (even if you can't actually hear it) or you are just wasting bandwidth. I hasten to add that I don't have any real clue what goes on in these regions and I would never claim to hear the difference. I am simply following the logic of the sampling theorem, here.
I sometimes comfort myself by thinking in octaves instead - that 96 kHz leap from 96 to 192 only requires another seven white keys on my Supersonic Steinway