Test results noise production
Noise is usually directly related to the cooling performance.
The Fractal Design Define R4 doesn't do great here, but it's not loud either.
With fans on low the Fractal Design Define R4 lands in the middle of the chart. A noise level of 32.9 dB(A) at a distance of 10 cm can be called quiet.
With fans on high the Define R4 claims one spot. 39.5 dB(A) is good, and the 140 mm fans definitely are an advantage here.