Noiseblocker NB-BlackSilent PRO PL-1 and PL-2
Fans from the German firm Noiseblocker have been discussed in our reviews before. Today I’m going to take a look at two new models: NB-BlackSilent PRO PL-1 and NB-BlackSilent PRO PL-2. The latter model doesn’t really fit into this review because its rated speed is 1400 RPM, but running a little ahead I can tell you that the NB-BlackSilent Pro PL-2 deservedly falls into this category of fans thanks to its surprisingly low level of noise.
These fans are packed into cardboard boxes with a cutout in the side panel. You can see some of the fan’s impeller and frame through it.
The package of each fan is most informative, detailing product specifications and key features. Included with each fan are screws and nuts for fastening, a soft vibration-absorbing frame with bushings in the corners, and two sleeved cables:
Each fan has a recommended price of $12.95 and comes with a 6-year warranty. They are manufactured in Germany.
The new models differ from the Noiseblocker NB-BlackSilent series in the design of both the frame (it is now solid and black) and the impeller.
The included soft frame is now used to suppress vibrations. The impeller is 112 millimeters in diameter. Three of the fan spokes are 5 millimeters wide; the cable spoke is 7 millimeters. The rotor is 44 millimeters in diameter. The fan weighs 120 grams.
The blades of this fan have a sharp front edge and a large angle of attack.
There are almost no ribs on the interior of the frame, which indicates the manufacturer’s desire to use every means available to reduce the noise. The rotation speed is constant at 900 RPM for the PL-1 and 1400 RPM for the PL-2. The air flow is 40 and 56.5 CFM, the static pressure is 0.761 and 1.296 millimeters of water, and the noise level is 11 and 20 dBA for the PL-1 and PL-2, respectively.
The new products from Noiseblocker do not differ from their predecessors in their internals. They run on a high-quality and energy-efficient motor NB-EKA Plus II, use expensive polymer materials and feature durable and noiseless bearings NB-NanoSLI. Quite a bunch of cutting-edge technologies within one small device! The sticker on each fan tells you the latter’s model name and rotation speed.
The Noiseblocker NB-BlackSilent Pro PL-1 boasts the longest rated service life among all the products in this review. It is as long as 180,000 hours! Its PL-2 cousin has a rated service life of 160,000 hours, which is impressive as well. The PL-1 is specified to consume no more than 0.72 watts and didn’t need more than 0.42 watts in my tests. That’s an excellent result. The PL-2 is specified to have a power draw of 1.92 watts and consumed 1.32 watts during my tests. These fans are supposed to have a start-up voltage of 4.5 volts but they could easily spin up at 4.1 and 3.9 volts, respectively. The two included cables are sleeved and have a length of 200 and 500 millimeters. The combined length is the longest among the 18 tested products.
Thus, the Noiseblocker NB-BlackSilent PRO PL-1 and PL2 are superior in every characteristic so far. Now let’s check out how they perform in terms of noise level and air flow.
The German fans are blameless. In my personal opinion, the Noiseblocker NB-BlackSilent PRO series are the most comfortable fans in this review in terms of noisiness. Perhaps “silence” may be too loud a word, yet I would dare call these fans silent until a speed of 900-950 RPM. Their extremely quiet operation deserves my praises, really. The Noiseblocker NB-BlackSilent PRO PL-1 and PL2 are not the leaders in terms of air flow, yet make it into the top four in this parameter as well.