I also heard good recordings made by similar little mics on shoulder under shirt.
Sometimes I place my CA-14 simply just above the collar/neck of a t-shirt. I "pull" out the mics to stay out of my t-shirt and thats it. Of course its amateur way but works, if you didnt move. And if you walked away after the show, put back under your shirt on your shoulders... get out again when the next starts.