Product Description
The NF-A14x25 G2 PWM Sx2-PP is a set of two NF-A14x25 G2 PWM 140mm square frame fans that are slightly offset in speed, which can be advantageous in push-pull operation as well as in situations where two fans are operated side by side, e.g. in case cooling applications or on 280mm water cooling radiators.
When two fans run at nearly the same, constant speed in a push-pull configuration or side-by-side, their acoustic interaction can lead to unwanted harmonic phenomena such as intermittent vibrations or periodic humming due to interference, which can be heard as beat frequencies. Therefore, the two NF-A14x25 G2 PWM fans included in the Sx2-PP set are slightly offset in speed (+/- ~25rpm) to avoid such phenomena. This fine-tuning is made possible by the fans' novel etaPERF™ motor and its NE-FD6 driver IC, which achieves extremely precise speed control and, thanks to its SupraTorque™ function, can utilize additional torque margin to maintain the desired speed even when working against significant flow resistance, such as on water cooling radiators and heat sinks.
Since one fan runs slower at ~25 rpm (PPA) and one runs faster at ~25 rpm (PPB), intermittent vibrations or periodic humming can be effectively prevented while maintaining the same overall cooling capacity. Especially since the perception of beat frequencies can vary depending on psychoacoustic preferences, users can easily further optimize the acoustics by running the PPA fan slightly slower via the PWM control or the included low-noise adapter, resulting in an even more pleasant noise signature due to the increased offset.
Double fan set for push-pull and side-by-side operation
The Sx2-PP set consists of two NF-A14x25 G2 PWM fans whose speed is offset by +/- ~25rpm to avoid unwanted acoustic interaction phenomena. It is the ideal choice for push-pull configurations as well as for situations where two fans are operated side by side, e.g. on 280mm radiators or in typical case cooling applications.
Next generation performance level
Noctua's renowned NF-A14 has received over 100 awards and recommendations from international trade publications and is considered one of the best 140mm fans on the market. With its even higher efficiency and new state-of-the-art design, the NF-A14x25 G2 represents a further innovation boost in terms of performance level and manufacturing technology.
Highly optimized P/Q characteristic curve for all applications
The advanced aerodynamic design of the NF-A14x25 G2 enables an extremely strong pressure/flow performance curve (P/Q), particularly in the critical mid-range. This makes the NF-A14x25 G2 a real all-rounder that works excellently in both pressure-sensitive and flow rate-sensitive applications.
Excellent application acoustics
While many fans produce unpleasant, high-pitched running noises as soon as they are mounted in...
