Products | Technologies | Support | Press | Reviews | Where To Buy

Smooth Commutation Drive

Next to aerodynamic noise and bearing related noises, the so called "commutation noise" or "switching noise" can play a major role in the noise emission of axial fans with brushless DC motors. At each transition from one stator coil to another, the rotor receives a sudden torque pulse when the next coil switches on. Each of these torque pulses causes a minute deformation of the whole fan structure. Depending on rpm, torque and the material of the fan, this can result in noticeable noises.

Noctua's Smooth Commutation Drive system provides more continuous switching in order to achieve a smoother transition between the stator coils and thereby significantly contributes to the fan's overall quietness. The second generation of this technology (SCD2) further improves running smoothness and reduces minute noises in close proximity to the motor.

24.07.2014 - PC Update NH-D15
Test verdict: "Pour qui a de la place ou n’aime pas les AiO, le Noctua NH-D15 est la nouvelle référence absolue en refroidissement par air." (Thomas Olivaux, PC Update)

24.07.2014 - NF-A14 industrialPPC-2000 PWM
Test verdict: "Como se esperaba, el precio de estos ventiladores IndustrialPPC es significativamente más alto. Pero si necesitas un ventilador duradero para tu servidor o sistema cotidiano, estos ventiladores son muy recomendables." (Zhiye Liu,

23.07.2014 - The Mod Zoo NF-F12 industrialPPC-3000 PWM
Test verdict: "I give the Noctua Redux and InustrialPPC fan lines five golden nanners for fantastic quality, renowned design and giving the nod to enthusiasts with appealing colors!" (Bill Owen, The Mod Zoo)

23.07.2014 - NH-D15
Test verdict: "The Noctua NH-D15 is an excellent, if not the best product currently available in the air cooling category" (Andrew James,