　Improving suction acoustics

Suction applications where fans draw air through obstacles such as grills or perforated panels can create turbulence that negatively affects acoustics. By introducing a 5 mm offset between the fan and the obstacle, NA-IS1 spacers help reduce intake turbulence and improve noise characteristics.

　More airflow, less noise

Reducing turbulence not only improves acoustics but also allows fans to operate more efficiently from an airflow perspective. In many intake setups, inlet spacers can help achieve higher airflow with lower noise levels.

　Compatible with Noctua 140×25 mm fans

The NA-IS1-14 replaces the fan’s stock NA-AVP1 anti-vibration pads and is compatible with Noctua square-frame 140×25 mm fans, such as:

NF-A14
NF-P14s redux

Note: Fans from other manufacturers are not supported.

　Set of 2 (Sx2)

The NA-IS1-14 Sx2 includes two spacer frames and mounting accessories, making it ideal for setups such as:

Two 140 mm intake fans at the front of a PC case
Two 140 mm fans on a 280 mm radiator in a front-intake configuration

　Anti-vibration mounts and fan screws

For case fan installations, the package includes:

8 × long self-tapping fan screws
8 × NA-AV3 silicone anti-vibration mounts

These allow tool-free installation while reducing vibration.

　Radiator screws included

For radiator installations, the set includes 35 mm radiator screws:

8 × M3 screws
8 × UNC 6-32 screws

This ensures compatibility with most water-cooling radiators.

　chromax.black version

The all-black chromax.black version perfectly matches black fans from Noctua’s chromax and industrialPPC product lines.

Product Name	Noctua NA-IS1-14 chromax.black Sx2
Type	Intake spacer frame
Compatible Fan Size	140 × 25 mm
Thickness	5 mm
Package Contents	Spacer ×2
Color	Black (chromax.black)
Material	PBT (Polybutylene Terephthalate)
Warranty	6 years

NA-IS1-14 chromax.black intake spacer frame ×2
NA-AV3 anti-vibration mounts ×8
Self-tapping fan screws ×8
Radiator screws (M3) ×8
Radiator screws (UNC 6-32) ×8

The level of intake turbulence varies depending on the fan model and installation environment (such as fan speed, grill shape, mesh pattern, and airflow resistance). Therefore, it is not possible to reliably predict the level of improvement that inlet spacers will provide.

While improvements in airflow and acoustics are common, some configurations may see little to no benefit. In rare cases, such as with certain slit-type grills, adding spacers may even produce undesirable results depending on the fan model.

The NA-IS1-14 chromax.black Sx2 is a set of two 5 mm thick intake-side spacer frames designed for Noctua 140×25 mm fans. It is developed for “pull” (intake) configurations where fans draw air through obstacles such as grills, mesh panels, filters, or radiators, helping to improve both cooling performance and acoustics.

By creating a small distance between the fan and the obstacle, the spacer reduces intake turbulence. This helps improve airflow efficiency while also lowering operating noise, resulting in smoother airflow and quieter fan operation.

The NA-IS1-14 is designed to replace the fan’s standard NA-AVP1 anti-vibration pads and is compatible with currently available square-frame Noctua 140×25 mm fans. Installation is simple: for case fan applications, the included self-tapping screws or NA-AV3 anti-vibration mounts can be used to secure the spacer between the fan and the case panel. For radiator installations, M3 and UNC 6-32 screws are included.

As a simple yet effective tuning accessory, the NA-IS1-14 helps improve airflow and reduce noise in intake-type fan setups. The chromax.black version is designed to perfectly match black fans from Noctua’s chromax and industrialPPC product lines.