Depends on how good the sex has been. Always a polite groan, but sometimes loud potty mouth as it tends to mean you boys go harder and faster ;-)
I'm generally quiet. I think it comes from stifling my sounds when wanking as a kid - at that time my preferred method was to hump the bed so the thrust was the same as sex. Then when I was older and having sex, more often than not the need for quiet was paramount lest we get caught. By the time I could have sex and not worry about making noise I was so conditioned to stifle any sound it was second nature. Of course then the kids came along...need I say more?
That's me in a nutshell. Perfect description!! Except I don't have kids yet.
it feels pretty nice