Typical of Noctua's packaging, the NF-F12 PWM comes in a white box with CAD drawings creating a subtle background, and a window allows you a glimpse at what is contained inside. The NF-F12 PWM has a book-style center section which details the various technologies and features found on their new fan.
The NF-F12 PWM also comes with a few accessories in addition to its user manual. A 30cm extension cable, a 4-pin Y-cable, and the low-noise adapter which reduces fan speed for even quieter operation. We can see Noctua's distinctive brown color running through its documentation, as well as the brown/beige color scheme seen on all of their fans.
The primary unique feature of the NF-F12 PWM is the "Focused Flow" stator guide vanes on the exhaust side of the fan. These stators are designed to straighten the highly-turbulent flow generated by the spinning blades. This aspect allows the flow to become more "focused" directly out in front of the blades, which means you'll have less flow spillage around the sides of the fan enclosure or the cooler you have the NF-F12 PWM attached to. This directly results in greater static pressures, which are critical to maximizing the flow between the fins of a heatsink or radiator. The stator vanes are also pitched at various angles so that each vane reacts to the flow differently, which may seem strange at first. Their reasoning isn't what you might first expect either, but given Noctua's reputation for making some of the quietest fans money can buy, it makes sense. The vanes are pitched differently so that each vane creates noise at a different frequency, meaning each frequency will have a lower overall amplitude, and you'll have quieter sound at a wider range of frequencies. This is a very unique approach by Noctua, and demonstrates their aggressive attitude to reduce noise as opposed to "only" optimizing the flow performance.
The vanes also feature what Noctua calls "Vortex Control Notches," which server a similar purpose to the stator guide vanes. The notches actually induce several smaller vortices, which "controls" the vortices which result on the tips of the blades, which also have the highest velocity. The vortices on the end of the spinning blades of a helicopter interacting with the other blades are what create the "chop-chop-chop" sound which gave helicopters the nickname "choppers." The same principle applies to case fans, and although it's less drastic because the enclosure helps to reduce the vortices on the blade tips, these vortices are still one of the primary sound sources. By using the notches to induce several smaller vortices, you allow each vortex to have a lower noise amplitude, and due to the changing interactions and radial distance from the hub, each notch will have slightly different tonal frequencies, distributing noise over a wider range of frequencies, each at a lower amplitude, leading to lower perceived noise.
The fan blades themselves use a proven design Noctua has used in the past, and the blade design is highly optimized for quiet operation. Noctua's renowned SSO2 bearings also mean you'll have low vibration, quiet operation, and also very long lifetimes, as would be expected being backed by a 6-year warranty. The corners of the fan chassis also have rubber anti-vibration pads, further evidence of the obsessive chase for a minimal acoustic footprint from Noctua.
Noctua's fan cables always come sleeved in a slick rubberized sleeving which is different than the fibrous sleeving you're probably used to. It's more of a hybrid rubber shroud which is heatshrinked to the cable ends. The sleeving looks very clean, but it is also a bit stiffer than traditional sleeving methods, but we believe the rubber sleeving should be more durable as well.