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Scythe Gentle Typhoon

The next family of Scythe fans that started selling in the end of last year is called Gentle Typhoon. And while the first word in the model name suits this solution pretty well, the second one doesn’t. But let’s start from the very beginning.

120 mm fans from Scythe Gentle Typhoon family are available in five different modifications and all of them will participate in our today’s test session. They ship in similarly designed boxes with different information printed on them. The plastic casing on the front of the box reveals the entire fan. You can also see the fan rotor through a cut-out round window in the back (below are the photos of the senior and the junior models in the lineup):

 

The package contains a lot of useful info about the fans inside, including not only their technical specifications, but also detailed description of the fan bearing with schematics. Gentle Typhoon fans are made in Indonesia and are priced at $16.96. Each fan is bundled with a Molex power adapter and four self-tapping screws.

The fans were originally designed by the Japanese Nidec Servo Company that have been working closely with Scythe for a long time now. Gentle Typhoon fans look very unusual and stand out among other fans due to black fan frame and nine dramatically curved light-gray blades attached to a large rotor:

They measure 119x119x25 mm and weigh 200 g. As I have already said, each fan has 9 blades and a rotor with 52 mm diameter. Just like all other developers, Nidec Servo Corporation tried to accomplish two goals when they designed Gentle Typhoon fans: to lower the noise and to increase the airflow intensity. According to the manufacturer, these fans are as efficient as 32 mm fans due to more blades with large sweep area:

 

Besides, unlike other Scythe fans, the inside of this fan frame is absolutely smooth, without any edges, and the side of the frame facing the incoming airflow has been rounded even more to lower the level of generated noise. Unfortunately, they didn’t manage to make the supporting rods thin and rounded because of pretty serious cable that goes into one of them, which slowed down the airflow a little.

Another peculiarity of Scythe Gentle Typhoon fans are the notches on the inside of the fan blades right next to the rotor:

The manufacturer didn’t explain their purpose, but I can only guess that these small notches around the fan rotor should probably create turbulent airflow. But for what purpose and why in this particular area? These notches are way too small to really affect fan operation in any way. They could probably lower the motor workload…

The rotation speeds of the fans in this lineup vary from 500 to 1850 RPM depending on the model (with 800, 1150 and 1450 RPM models in-between). The declared airflow is measured in cubic meters per hour and ranges from 31 to 99, which translates into CFM as 17.7-56.5 CFM. As you can see, there is nothing supernatural about the airflow by Scythe Gentle Typhoon fans. There is no mention of the fans’ static pressure, but they do reveal the noise readings: 5 dBA for the junior model and 28 dBA by the senior one. Taking into account that the top model works at 1850 RPM rotation speed, the claimed 28 dBA of noise is very little.

Scythe Gentle Typhoon fans have the largest rotor diameter of all fans tested today – 52 mm. It is more likely the result of a double ball bearing employed in them, each balanced manually. Together with the frame and fan blades design, the bearing was built to produce noise in a specific acoustic range that is not perceived by the human ear.

Besides, ideally balanced fans shouldn’t transfer vibrations onto the case parts. The manufacturers claim that Gentle Typhoon fans won’t stand out against the noise of the working system power supply (though they don’t state which one). The bearings have 100,000 hours of MTBF at 30 °C or 60,000 hours at 60 °C, which is more than enough for these fans to outlive several system cases.

They haven’t forgotten to mention the fan electronics either. The manufacturer claims that Gentle Typhoon consumes 30% less power than other fans due to high efficiency of the motor. According to the technical specifications, the developers did succeed here, because even the top model in the family should consume no more that 1 W at 0.083 A current. And that is at 1850 RPM rotation speed! It is very impressive, although not so utterly important, considering how tiny this number is against the background of the rest of the system case. The fans startup voltage is the following: 500 RPM – 6.5 V, 800 RPM – 5.5 V, 1150 RPM – 4.5 V, 1450 RPM and 1850 RPM – 3.5 V.

There is a sticker on the rotor of each fan that has the fan model number and some other details printed on it:

  

 

In conclusion to our review of Scythe Gentle Typhoon fans I would like to add that the fan frames have short stands in the corners between the retention holes. These stands may become a problem during fan installation onto cooler heatsinks that require attaching the fans by the inside of the fan frame opening. Besides, the 300 mm cable could have been a little longer. The fans are priced at about $17.

Let’s take a look at their performance:

Well, these are 5 more great fans from Scythe, no doubt about that. Gentle Typhoon demonstrated excellent acoustics, so they can work at higher rotation speed generating about the same noise as their competitors. For example, they work within acoustically comfortable range at about 1440 RPM – an unattainable speed for other solutions. Had their rotor been not so humongous, they could have become indisputable leaders not only in acoustics but also in airflow tests. And at this point, unfortunately, 52 mm rotor eats away the effective sweep area from the fan blades that is why Scythe Gentle Typhoon becomes only one of the best, which is also quite rewarding. We didn’t register any parasitic noises coming from the motor or bearing during the entire test session. Only when we changed the fan rotation speed, we could hear some short-term clanging sound that would disappear only when the rotation speed became constant. Scythe Gentle Typhoon fans boast undoubtedly the best power consumption: even the most powerful model consumes less than 1 W of power. The interesting thing is that the fan blades keep spinning for about 30-35 seconds once the power has been shut off – it is a great illustration of how well-balanced the bearing is. The startup voltages for all five fans are: 6.9, 5.4, 3.0, 3.9 and 3.6 V.

 
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