In our noise level tests we switched off all the case fans and replaced the AMD Radeon HD 7950 graphics card with a HD 5550 passive model so were just taking into account the noise generated by the cooler fans themselves.
We measured the noise level with a Digital Noise Level meter at a distance of 1 m from the front of the system.
We can see that the Kuhler 1250 is very quiet in silent mode, however the noise increases exponentially in Extreme mode and becomes very loud.