An other vid. We can easily heard the sound of the bow. It's seems like if it was vibration.

the first bow (where is written "volume normal", is the normal sound), for the "reprise, volume emplifié", is the sound turn-up a little bit, and the last one is turn-up, but to the maximum.
http://www.youtube.com/watch?v=SzvW4eUy8x8

Thanks to help me! Your THE forum for the archery, and i'm learning english here too

Francis