Test Methodology
I use an LW-9266 Fan PQ performance measurement apparatus to evaluate cooling fans. This highly sophisticated scientific instrument was made in Taiwan by Long Win.
Fan Testing Machine Technical Specifications:
- Manufacturer: Long Win Science & Technology Corporation
- Air Flow Rate: 2.4 – 250 CFM
- Accuracy of Air Flow Rage: <3.5% INFS
- Repeatability error: < 2%
- Static pressure: 0-20mmAq (100mmAq with the high static pressure throttle device)
- Overall Dimensions: 0.7 (W) x 2.2 (L) x 1.6 (H) m
- Power Source: 220VAC, 5A, Single Phase, 50/60Hz
- Based on Standards: ISO 5801-2007, AMCA 210-0, ASHRAE 51-2007, IEC 61591-2005, GB/T 1236-200
Besides the Long Win machine, I also use the following equipment.
Testing Equipment:
- Noise Test Environment: Hemi-Anechoic Chamber with 6 dB(A) noise floor
- Conditions: 25 (+-2) degrees Celsius, 40-50% humidity
- Sound Analyzer: Bruel & Kjaer 2270-S G4
- Microphone: Bruel & Kjaer Type 4955-A
- Mic Calibrator: Bruel & Kjaer Type 4231
- Data Logger: Picoscope TC-08
Pages:
Is that secondary impeller noticeably adding harmonics, particularly that major 3rd? I’m actually curious if this thing has sound design characteristics I might want to experiment with.
please check the frequency analysis I conducted for that.
Hi @crmaris can you please tell me what size screws I would need to mount this fan on an AIO radiator?
It is 38mm thick so 45mm long I would say.
Besides the thickness, is there any reason the home enthusiast should not consider these the best watercooling radiator fans for low noise? Less optimal noise frequencies than its competitors?
The thickness is the major issue for most cases, with limited internal space.
That mechanical clicking in the low speed recording sounds like it could get *pretty* irritating.
As someone who tried using these (8K variant) fans for home PC cooling, I can confirm that clicking noise is VERY irritating already at ~1K RPM. I bought pack of 3, and each of them sounded like this – mounted, not mounted, held by hand, etc. Clicking becomes tolerable around 400-500 RPM, but listening closely they’re still pretty noisy compared to others, and at this point there’s no advantage in using these fans over anything that came pre-installed with case. Too bad, because overall they’re really cool and with such static pressure would be perfect for a crowded PC.