Noctua NA-IS1-14 Sx2, Inlet Side Spacers for 140mm Fans

The NA-IS1-14 Sx2 is a set of two 5mm thick intake side spacer frames for Noctua 140x25mm fans that can help to improve both acoustics and performance in suction or “pull” type applications where the fan draws air through obstacles such as grills, perforated plates, mesh panels, filters or radiators. By offsetting the fan from the obstacle, the NA-IS1 inlet spacer reduces influx turbulences, which can, depending on the application and fan model, not only improve airflow but also significantly reduce overall noise levels and make the fan sound more pleasant to the ear. Designed to replace the fan’s stock NA-AVP1 anti-vibration pads, the NA-IS1-14 are compatible with all current square-frame Noctua 140x25mm fans and extremely straightforward to install: For case fan applications, either the supplied self-tapping screws or the included NA-AV3 anti-vibration mounts can be used to sandwich the spacer between the fan and the case panel. For radiator mounting, both M3 and UNC 6-32 screws are supplied. In sum, the NA-IS1-14 Sx2 set is a simple yet highly effective fine-tuning measure for suction type applications where a reduction of influx turbulence can lead to improved airflow and acoustics.

Improving suction acoustics

Suction applications where fans draw air through obstacles such as grills or perforated panels are notoriously challenging acoustically due to the turbulences caused by these obstacles. Introducing a 5mm off-set between the fan and the obstacle, the NA-IS1 spacers can reduce these turbulences, which often improves noise levels and/or noise profiles significantly.

More airflow, less noise

Reducing influx turbulences doesn’t only improve acoustics, it also helps fans to operate more efficiently from an airflow performance point of view because the fan blades are less hampered by turbulence. In many suction type applications, using inlet spacers can therefore enable fans to achieve higher flow rates and lower noise emissions at the same time.

Compatible with all current Noctua 140x25mm fans

Replacing the fan’s stock NA-AVP1 anti-vibration pads, the NA-IS1-14 are compatible with all current Noctua square-frame 140x25mm fans such as the popular NF-A14 or NF-P14s redux series. Fans from other manufacturers are not supported.

Set of 2 (Sx2)

The NA-IS1-14 Sx2 is a set of two spacer frames plus the matching anti-vibration mounts, fan screws and radiator screws – ideal for equipping e.g. two 140mm intake fans in the front of a PC case or two 140mm fans on a 280mm radiator that’s installed in a front intake position.

Anti-vibration mounts and fan screws

For use with case intake fans, the NA-IS1-14 Sx2 contains eight long self-tapping fan screws and eight NA-AV3 silicone anti-vibration mounts for tool-free, vibration-proof installation. Both the screws and the anti-vibration mounts simply go through the holes in the spacer and attach to the fan, sandwiching the spacer between the fan and the case.

Radiator screws

For use with water cooling radiators, the NA-IS1-14 Sx2 contains 35mm long radiator screws, eight pieces with M3 thread and eight pieces with UNC 6-32 thread so that customers can choose the correct type for their radiator.

Notes and warnings

Caution: As influx turbulences vary between different fans models and setups (e.g. different fan speeds, grill shapes, mesh patterns, overall flow resistance, etc.), it is not possible to reliably predict how much of an improvement adding inlet spacers will make. While the improvements are significant in most configurations, there sometimes may be little to no improvements and, in rare situations such as with particular slit-type grills, adding spacers may even lead to undesirable results with particular fan models.

Please see our performance guidelines for further information. If in doubt, detach the fan from your application, then hold it in place with no distance first and 5mm distance next. This will give you a rough indication of how much improvement you can expect in your individual configuration.