Last fall, we both bought DAS Keyboard Ultimate keyboards with Cherry MX Blue switches. While Fred seems to be a fairly light typist, I can make a lot of noise with my keyboard. It turns out that I am bottoming out (hitting the bottom of the keyboard) on each stroke, which is loud. Seriously, loud. It also feels hard on my hands, because your finger travels a bit further and then abruptly stopped.
To combat this, we both ordered o-ring dampeners and installed them.