The NF-A9 differs greatly from the NF-B9, as you can see:
All Noctua premium fans come encased in a plastic shock-absorbing shell. With the clear plastic cover off, the NF-A9 looks like this:
In the second picture you can see the various features of Noctua’s A Series -- the AAO, the stepped inlet, for example. Of the inlet, Noctua says:
One can also see the Flow Acceleration Channels and the Inner Surface Microstructures that will be constant features of all these fans. Of the flow acceleration channels, Noctua says:
You can really see the Inner Surface Microstructures.
As noted previously, each fan has a custom set of accessories. By looking at the more important accessories, one can see how accessories for an NF-A9 FLX differ from accessories for an NF-A9 PWM.
All Noctua premium fans come encased in a plastic shock-absorbing shell. With the clear plastic cover off, the NF-A9 looks like this:
In the second picture you can see the various features of Noctua’s A Series -- the AAO, the stepped inlet, for example. Of the inlet, Noctua says:
Our Stepped Inlet Design adds turbulence to the influx in order to facilitate the transition from laminar flow to turbulent flow, which reduces tonal intake noise, improves flow attachment and increases suction capacity, especially in space restricted environments.
One can also see the Flow Acceleration Channels and the Inner Surface Microstructures that will be constant features of all these fans. Of the flow acceleration channels, Noctua says:
By speeding up the airflow at the crucial outer blade regions, Flow Acceleration Channels reduce suction side flow separation and thus lead to better efficiency and lower vortex noise.
You can really see the Inner Surface Microstructures.
As noted previously, each fan has a custom set of accessories. By looking at the more important accessories, one can see how accessories for an NF-A9 FLX differ from accessories for an NF-A9 PWM.
