i am still new to electronic and i probably have a stupid question..
i am trying to build a buffer for a piezo microphone following the project on this site: http://www.scotthelmke.com/Mint-box-buffer.html
but now i am wondering how to make the input of this circuit balanced, to connect two piezo mic in a coupled structure like this http://www.instructables.com/id/Balanced-piezo-contact-microphones/
is it possible to modify this circuit ? or do i need something new ?? thanks ! :)