Award-winning NF-A12x25 impeller
Noctuas NF-A12x25 has captured the hearts of quiet cooling enthusiasts around
the world and reshaped the common perception of what 120mm fans can do. With
more than 100 awards and recommendations from the international press, it is
widely considered to be the best 120mm fan on the market. The NF-A12x25r
combines the same impeller with a round frame.
Round frame design
The NF-A12x25r is identical to the NF-A12x25 except for its round frame that
allows it to be used in applications where a square-frame 120mm fan would not
fit. For example, the NF-A12x25r is ideal for being sunk in between the dual
towers of the low-height NH-D12L cooler without causing compatibility problems
with tall motherboard heatsinks or shrouds.
Next-generation performance
Noctuas 120mm fans such as the NF-F12 and NF-S12A are renowned as being among
the best on the market and have received more than 400 awards and
recommendations from the international press. With its further improved
efficiency and novel, state-of-the-art engineering, the NF-A12x25 represents
another step up in performance and manufacturing.
Highly optimised P/Q curve for all
applications
The NF-A12x25s sophisticated aerodynamic design allows for a pressure to
airflow (P/Q) curve that is extremely strong in the critical mid-section. This
means that the NF-A12x25 is a true jack-of-all-trades with excellent performance
in both static pressure demanding and airflow demanding applications.
Excellent on-application acoustics
While many fans produce unpleasant, high-pitched noises when installed in
typical applications such as on heatsinks or radiators, the NF-A12x25 has been
carefully fine-tuned for optimal on-application acoustics. It produces a smooth,
pleasant frequency profile and surprisingly low sound pressure levels (SPL) when
working against back pressure.
Flow Acceleration Channels
The NF-A12x25 impeller features suction side Flow Acceleration Channels. By
speeding up the airflow at the crucial outer blade regions, this measure reduces
suction side flow separation and thus leads to better efficiency and lower
vortex noise.
Ultra-tight tip clearance
The NF-A12x25 has a record tight tip clearance (distance between the blade
tips and the inside of the frame) of only 0.5mm. This highly ambitious design
sets a new benchmark for 120mm fans and helps the NF-A12x25 to work more
efficiently against back pressure, such as on heatsinks or radiators, by
reducing leak flows through the gap between impeller and frame.
Metal-reinforced motor hub
The centrepiece of the NF-A12x25s motor hub is made entirely from steel and
the axle mount is reinforced with an additional brass structure. In combination,
both measures ensure ultimate precision and increased stability in the critical
hub area.
Sterrox liquid-crystal polymer compound
The NF-A12x25s impeller is made from Noctuas novel Sterrox liquid-crystal
polymer (LCP) compound that features extreme tensile strength, an exceptionally
low thermal expansion coefficient and damping characteristics that are ideal for
reducing resonance and vibration phenomena in advanced fan-blade designs.
AAO frame
Noctua's AAO (Advanced Acoustic Optimisation) frames feature integrated
anti-vibration pads as well as Noctua's proprietary Stepped Inlet Design and
Inner Surface Microstructures, both of which further refine the fan's
performance/noise efficiency.
Stepped Inlet Design
Noctua's Stepped Inlet Design adds turbulence to the influx in order to
facilitate the transition from laminar flow to turbulent flow, which reduces
tonal intake noise, improves flow attachment and increases suction capacity,
especially in space-restricted environments.
Inner Surface Microstructures
With the tips of the fan blades ploughing through the boundary layer created
by the Inner Surface Microstructures, flow separation from the suction side of
the blades is significantly suppressed, which results in reduced blade passing
noise and improved airflow and pressure efficiency.
Integrated anti-vibration pads
Integrated anti-vibration pads made from extra-soft silicone minimise the
transmission of minute vibrations while maintaining full compatibility with all
standard screws and other mounting systems.
SSO2 bearing
The NF-A12x25 features the further optimised second generation of Noctua's
renowned, time-tested SSO bearing. With SSO2, the rear magnet is placed closer
to the axis to provide even better stabilisation, precision and durability.
Metal bearing shell
In order to guarantee the highest possible degree of manufacturing precision,
minimum tolerance and excellent long-term stability, the NF-A12x25 sports a CNC
milled bearing shell made entirely from brass.
Custom-designed PWM IC with SCD
Supporting fully automatic PWM speed control, the fan uses Noctua's
custom-designed NE-FD1 PWM IC that integrates Smooth Commutation Drive (SCD)
technology. By providing smoother torque impulses, SCD suppresses PWM switching
noises and thus makes the fan quieter at low speeds.
Stops at 0% PWM
When the fan is set to 0% PWM duty cycle by the motherboard or PWM fan
controller, it will stop. This makes it ideal for creating setups with
semi-passive cooling that automatically turn the fans off and thus run
completely silent at idle if thermals allow.
Smooth Commutation Drive 2
The latest version of Noctua's advanced Smooth Commutation Drive system
ensures superb running smoothness by eliminating torque variations and switching
noises. This makes the fan remarkably quiet even at very close distances.
Low-Noise Adaptor
The NF-A12x25 PWM is supplied with a Low-Noise Adaptor (L.N.A.) that reduces
the maximum fan speed from 2000 to 1700rpm. The L.N.A. can be used either to run
the fan at a fixed speed of 1700rpm or to cap the maximum speed when using
automatic PWM control.
Extensive cabling options
The fan's short 20cm primary cable minimises cable clutter in typical
applications while the supplied 30cm extension provides extended reach when
necessary. Both cables are fully sleeved and a 4-pin y-cable allows the
connection of a second fan to the same PWM fan header for automatic control.
6-year manufacturers warranty
Noctua fans are renowned for their impeccable quality and outstanding
longevity. Like all Noctua fans, the NF-A12x25 features an MTTF of more than
150.000 hours rating and comes with a full 6-year manufacturers warranty.
Notes and warnings Caution:
The round-frame NF-A12x25r features a custom hole spacing of 93x83mm.
Therefore, it is not suitable for applications that require the standard
105x105mm hole spacing of square-frame 120mm fans such as PC cases,
water-cooling radiators or CPU coolers with fan clips for square-frame 120mm
fans. Please choose the regular, square-frame NF-A12x25 for these
applications.
Specifications
|
Size |
120x120x25
mm |
|
Mounting
hole spacing |
93x83
mm |
|
Connector
& pin-configuration |
4-pin
PWM |
|
Cable
length |
20cm
+ 30cm NA-EC1 extension cable |
|
Bearing |
SSO2 |
|
Blade
geometry |
A-Series
with Flow Acceleration Channels |
|
Frame
technology |
AAO
(Advanced Acoustic Optimisation) |
|
Material |
Sterrox
LCP |
|
Rotational
speed (+/- 10%) |
2000
RPM |
|
Rotational
speed with L.N.A. (+/- 10%) |
1700
RPM |
|
Min.
rotational speed @ 20% PWM (+/-20%) |
450
RPM |
|
Airflow |
102,1 m/h |
|
Airflow
with L.N.A. |
84,5 m/h |
|
Acoustical
noise |
22,6
dB(A) |
|
Acoustical
noise with L.N.A. |
18,8
dB(A) |
|
Static
pressure |
2,34
mm HO |
|
Static
pressure with L.N.A. |
1,65
mm HO |
|
Max.
input power |
1,68
W |
|
Max.
input current |
0,14
A |
|
Operating
voltage |
12
V |
|
Voltage
PWM signal |
5
V |
|
MTTF |
>
150.000 h |
|
Scope
of delivery |
NA-RC14
Low-Noise Adaptor (L.N.A) |
|
NA-YC1
4-pin PWM y-cable |
|
NA-EC1
30cm extension cable |
|
4x
NA-AV2 anti-vibration mounts |
|
Fan
screws |
|
Warranty |
6
years |
