First off, not all women make noise or are vocal during sex. Others are. And the same goes with men. Some men are very vocal during sex and others aren't. As for sensation...the inside of the vagina has very little sensation which is why it is very hard for a woman to climax from missionary style sex alone. As for being more vocal, it is because for the most part, women are more comfortable w/expressing themselves. Some women may be copying what they have seen/heard on porn as well. You have to remember that if the woman is on the bottom and the man is on top and pushing into her, each thrust is forceful, and your breathing is heavier due to sexual excitation, then w/each thrust, sometimes the breath gets pushed out of you more forcefully then it would be if someone wasn't doing this thrusting motion into you.