Noctua NF-A14x25r G2 PWM Sx2-PP

Dedicated push-pull set (Sx2-PP) with two round-frame NF-A14x25r G2 PWM 140x25mm fans that are slightly off-set in speed (+/- ~25rpm) in order to avoid undesired acoustic interaction phenomena State-of-the-art engineering (Progressive-Bend impeller with winglets and Centrifugal Turbulator, Flow Acceleration Channels, AAO frame) and construction (S... moreterrox LCP, ultra-tight tip clearance) Ideal choice for push-pull applications on 14cm CPU coolers such as the NH-D15, NH-D15S or NH-U14S series, next-generation quiet cooling performance with unprecedented acoustic fine-tuning measures Includes anti-vibration mounts, fan screws, Low-Noise Adaptors (LNA), extension cables and y-cable for running two fans on the same header Trusted Noctua quality with premium-grade SSO2 bearing (MTTF > 150,000 h), safety certifications from UL and TÜV, protected against reverse polarity, over voltage and over current (short-circuits)

The NF-A14x25r G2 PWM Sx2-PP is a set of two NF-A14x25r G2 PWM round-frame 140mm fans for push-pull operation on heatsinks such as the NH-D15(S) or NH-U14S. When two fans operate in a push-pull configuration running at almost the same, constant speed, their acoustic interaction can lead to undesirable harmonic phenomena such as intermittent vibrati... moreons or periodic humming due to interference, which can be heard as beat frequencies. Therefore, the two NF-A14x25r G2 PWM fans contained in the Sx2-PP set are slightly offset in speed (+/- ~25rpm) in order to avoid such phenomena. This fine-tuning is made possible by the fans' novel etaPERF™ motor and its NE-FD6 driver IC that achieves extremely precise speed control and, thanks to its SupraTorque™ feature, can leverages extra torque headroom to keep the exact desired speed even when working against significant flow resistance such as on heatsinks. 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. Since the perception of beat frequencies can vary depending on psychoacoustic preferences, users can easily further optimise acoustics by slowing the PPA fan down a little more through PWM control or the supplied Low-Noise-Adaptor, which will result in an even smoother sound signature due to the increased offset.Specifications:- Size: 140x140x25 mm- Mounting hole spacing: 105x105 mm- Connector & pin-configuration: 4-pin PWM- Cable length: 20cm + 30cm NA-EC1 extension cable- Bearing: SSO2- Blade geometry: Progressive-Bend impeller- Frame technology: AAO (Advanced Acoustic Optimisation)- Material: Sterrox® LCP- Rotational speed (+/- 10%): 1500 RPM- Rotational speed with L.N.A. (+/- 10%): 1250 RPM- Airflow: 155.6 m³/h- Airflow with L.N.A.: 127.1 m³/h- Acoustical noise: 24.8 dB(A)- Acoustical noise with L.N.A.: 19.7 dB(A)- Static pressure: 2.56 mm H₂O- Static pressure with L.N.A.: 1.3 mm H₂O- Input power (max.): 2.28 W- Max. input current: 0.19 A- Operating voltage: 12 V- Voltage PWM signal: 5 V- MTTF: > 150,000 hScope of delivery: - NF-A14x25r G2 PWM PPA- NF-A14x25r G2 PWM PPB- 2x NA-RC16 Low-Noise Adaptor (L.N.A.)- NA-YC1 4-pin PWM splitter cable- 2x NA-EC1 30cm extension cable- 8x NA-AV2 anti-vibration mounts- Fan screwsTechnology:Push-pull set:- Bundling two NF-A14x25r 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 on 140mm class coolers such as the NH-D15(S) or NH-U14S.Next-generation performance:- Noctua's NF-A15 is renowned as being among the best round-frame 140mm fans on the market and has received more than 100 awards and recommendations from the international press. With its further improved efficiency and novel, state-of-the-art engineering, the NF-A14x25r G2 represents another step up in performance and manufacturing.Highly