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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.

09.10.2015 - NH-D9L
Test verdict: "Akhir kata, mirip seperti Noctua NH-U9S, Noctua NH-D9L adalah sebuah heatsink fan dengan build quality baik, fan 92mm yang cukup hening, berukuran cukup ringkas, namun masih bertenaga untuk menangani sebuah Core i7-4790K yang dioverclock pada 4.5Ghz atau lebih." (Alva Jonathan,

08.10.2015 - NH-U9S
Test verdict: "Jika Anda menginginkan sebuah PC mini dengan prosesor yang powerful, dan masih bingung memilih heatsink yang memiliki ukuran kecil dan performa baik, Noctua NH-U9S bisa masuk dalam pertimbangan Anda." (Alva Jonathan,

08.10.2015 - Formula Hardware NF-P14s redux-1500 PWM
Test verdict: "Por lo tanto, bajo nuestro punto de vista, estamos ante unos productos de gran rendimiento, gran calidad, y sin duda alguna, son ventiladores totalmente recomendados." (Asis Ferrer, Formula Hardware)

08.10.2015 - NH-D15S
Test verdict: "Hält der Noctua NH-D15S also was er verspricht beziehungsweise was man von ihm erwartet? Die Testergebnisse sprechen wohl eine eindeutige Sprache und sagen klar und deutlich: Ja!" (Tobias Guttmann,