I have a K40 and a B60. The K40 is whisper quiet but the the B60 sounds like it's going to shake itself apart when it's drawing water in from the reservoir. I de-scaled it by running a pint of white vinegar through it, which helped a little bit. I also swapped the k40's all plastic drip tray onto the B60 in place of its tray, which has a stainless steel insert. That dropped it another decibel or two but it's still pretty loud. I'm tempted to either replace the main pump motor or figure out some way to dampen the vibration like maybe rubber grommets on the the motor's mounting bracket.