BeQuiet! Pure Wings 2 (BL039): It wouldn’t do without the grooves

BeQuiet! Pure Wings 2 (BL039) in detail

So, now we get to see what the grooves on the entire surface of the blades, which are typical of BeQuiet! fans, are worth! Judging by the geometry, we were initially concerned that the results might go in a similar direction to the Arctic BioniX F120. But it’s a lot better than that, and the 120 mm Pure Wings 2 even achieves a top price/performance ratio while running very quietly. The best of the fans tested so far.

Evalutaion

The Pure Wings 2 is more efficient in system fan positions than on radiators. However, given the low price, it cannot be argued that use on a radiator would be inappropriate. Especially when combined with a thinner radiator or cooler heatsink (and BeQuiet! mounts them on such models within their coolers) the results are at a similar level to the SilentiumPC Fluctus 120 PWM or Noctua NF-P12 redux-1700 PWM fans. However, the thicker the radiator is used and the higher the speed is set, the lower the efficiency (or cooling power-to-noise ratio) of the Pure Wings 2 is.

The Pure Wings 2 can deliver better, even elite results as a system fan. Theoretically, with no obstacles, it is at the very top. But only at very low speeds. The airflow drop across the quietest test modes of 33 and 31 dBA is significantly lower than other fans, which makes this fan extremely attractive at around 630 rpm. And that’s basically even in a more practical deployment. Nothing fundamental changes even with the use of a plastic filter.

Airflow with a filter, as with all fans, naturally decreases, but the ranking is still excellent, right behind the considerably more expensive MSI MEG Silent Silent Gale P12. With higher speeds, the efficiency of the Pure Wings 2 drops, but in the mid-band it is still decent, comparable to the Noctua NF-P12 redux-1700 PWM. And that’s even when operating on a hexagonal grille.

The disadvantage of the Pure Wings 2 is that you cannot fit a regular dust filter with a nylon mesh directly onto it. The motor housing is very close, which results in contact and an unpleasant rustling sound. However, nylon filter designs with a reinforced mesh on the inside (typically a cross) will be satisfactory. Additionally, in many cases, the filters keep their distance from the fans (for example, when they are up to mask level and the fan is a good few centimetres behind them), which are also applications where the BeQuiet! fan fits.

The strength of Pure Wings 2 lies in its always pleasant acoustic presentation. In fact, it never happens that any of the sound frequencies permeate unpleasantly (so yes, the multi-purpose grooving has a definite justification). And not even with a hexagonal grille, where the rival Noctua NF-P12 redux doesn’t fare too well in this regard. Pure Wings 2 doesn’t have such a robust motor and things around it (massive spindle, bearings, etc.), but these designs have one thing in common – very low manufacturing tolerances with high precision.

At maximum speed, vibrations are borderline undetectable, even with our ultra-sensitive system. Between 1050–1200 rpm, while some Y-axis vibration does occur, it can still be classified as negligible, and importantly, doesn’t make life unpleasant in the most efficient fan speed range, below 1000 rpm. BeQuiet! does not disclose minimum speed information in the specifications, but it is not something that has to remain a secret. The Pure Wings 2 with the BL039 designation can steadily slow down to 350 rpm, which is also the starting speed.

Also worth mentioning with this fan is the very low power draw and the resulting top-notch airflow per watt coefficient. This is especially the case in the most aerodynamically efficient and quietest mode of 31 dBA, where only the Gigabyte Aorus 120 ARGB stands ahead of the Pure Wings 2. But this one is particularly helped in low speed settings by having more (6) stator slots than the BeQuiet! fan has (4). However, it’s not that the few milliwatts that the Pure Wings 2 is more efficient than other fans at the same airflow will save you anything. That’s irrelevant. What is relevant with this parameter is that it points to the low friction inside the fan. This means that the load on the “rifle” bearings (technologically basically sleeve), which on paper don’t look as good as the “SSO” bearings on Noctua redux fans, is also lower.

You now know the BeQuiet! Pure Wings 2 (BL039)’s profile, and hopefully you won’t object when we give it, for an attractive price-to-value ratio (which is not only made up of decent cooling efficiency with high airflow per euro) the „Smart buy!“ award.

English translation and edit by Jozef Dudáš

• Contents
• BeQuiet! Pure Wings 2 (BL039) in detail
• The basis of the methodology, the wind tunnel
• Mounting and vibration measurement
• Initial warm-up and speed recording
• Base 7 equal noise levels…
• .. and sound color (frequency characteristic)
• Static pressure measurement…
• … and airflow
• Everything changes with obstacles
• How we measure power draw and motor power
• Measuring the intensity (and power draw) of lighting
• Results: Speed
• Results: Airlow w/o obstacles
• Results: Airflow through a nylon filter
• Results: Airflow through a plastic filter
• Results: Airflow through a hexagonal grille
• Results: Airflow through a thinner radiator
• Results: Airflow through a thicker radiator
• Results: Static pressure w/o obstacles
• Results: Static pressure through a nylon filter
• Results: Static pressure through a plastic filter
• Results: Static pressure through a hexagonal grille
• Results: Static pressure through a thinner radiator
• Results: Static pressure through a thicker radiator
• Results: Static pressure, efficiency by orientation
• Reality vs. specifications
• Results: Frequency response of sound w/o obstacles
• Results: Frequency response of sound with a dust filter
• Results: Frequency response of sound with a hexagonal grille
• Results: Frequency response of sound with a radiator
• Results: Vibration, in total (3D vector length)
• Results: Vibration, X-axis
• Results: Vibration, Y-axis
• Results: Vibration, Z-axis
• Results: Power draw (and motor power)
• Results: Cooling performance per watt, airflow
• Results: Cooling performance per watt, static pressure
• Airflow per euro
• Static pressure per euro
• Results: Lighting – LED luminance and power draw
• Results: LED to motor power draw ratio
• Evaluation