Noctua NF-A14x25 G2 PWM Sx2-PP, Dual Fan Set for Push-Pull and Side-by-Side Applications (Brown)

The NF-A14x25 G2 PWM Sx2-PP is a set of two NF-A14x25 G2 PWM square-frame 140mm fans that are offset in speed, which can be beneficial in push-pull operation as well as in situations where two fans are operating side by side, such as in case cooling applications or on 280mm water cooling radiators. When two fans are running at almost the same, constant speed in a push-pull configuration or, albeit to a lesser extent, side by side, their acoustic interaction can lead to undesirable 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 contained in the Sx2-PP set are slightly offset in speed (+/- ~25rpm) in order to avoid such phenomena. With one fan running ~25rpm slower (PPA) and one ~25rpm faster (PPB), the overall cooling performance can be kept the same while efficiently preventing intermittent vibrations or periodic humming. Dual fan set for push-pull and side-by-side usage Bundling two NF-A14x25 G2 PWM fans that are speed-offset by +/- ~25rpm in order to avoid undesired acoustic interaction phenomena, the Sx2-PP set is the ideal choice for push-pull configurations as well as situations where two fans are operating side by side such as on 280mm radiators or in typical case cooling applications.

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