The NF-S12A features the third evolution of Noctua's classic Straight Blade Design that achieves 10 cfm The NF-S12A's Anti-Stall Knobs reduce flow separation phenomena in medium to high impedance situations n thereby increase the fan's stall margin, that is even more versatile than its renowned predecessor . Noctua's AAO (Advanced Acoustic Optimization) frames feature integrated anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and Inner Surface Microstructures, both of which further refine the fan's performance/noise efficiency. Noctua's Stepped Inlet Design adds turbulence to the influx to facilitate the transition for laminar flow to turbulent flow, that reduces tonal intake noise, improves flow attachment, incur suction capacity, especially in space restricted environments. Integrated Anti-Vibration Pads made from extra-soft silicone minimize the transmission of minute vibrations while maintaining full compatibility with all standard screws and other mounting systems. The NF-S12A marks the third generation of Noctua's signature S12 series quiet case fans, which have received more than 250 awards and recommendations from the international press. Featuring a further refined blade design with Anti-Stall Knobs that works in tandem with the new AAO (Advanced Acoustic Optimization) frame, the NF-S12A improves the airflow/noise efficiency of its renowned predecessor by up to 8%. The PWM version sports Noctua's custom designed NE-FD1 IC for fully automatic speed control via 4-pin fan headers and comes with a Low-Noise-Adaptor to reduce the maximum speed during PWM control from 1200 to 900rpm. Its superb running smoothness, SSO2 bearing and Noctua's trusted premium quality make it an elite choice for quiet case cooling.
I have a new AirStream trailer and the Dometic refrigerator has a cooling chimney of sorts with access from outside. There is a lower vent door where cool air comes in and a higher vent door where the hot air is expected to exit with the help of a rather noisy fan that comes on when the cooling fins get hot. On our first outing, the fan noise nearly drove my wife and I nuts. I added rubber isolating gaskets to the fan, but that only dropped the noise by 40%. Af..