I have used RTA's for my home theater and for sound reinforcement applications before.
I have the system sounding really good for the most part by adjusting to my ear and my favorite cuts.
I got the microphone at amazon per
Dirtboy
Here it is.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
The more people that give feedback, potentially the better. Thanks for the wi-fi info. I will check it out.