The Logitech G910 Orion Spectrum Mechanical Keyboard Reviewby E. Fylladitakis on October 6, 2016 8:30 AM EST
Per-Key Quality Testing
In order to test the quality and consistency of a keyboard, we are using a texture analyser that is programmed to measure and display the actuation force of the standard keyboard keys. By measuring the actuation force of every key, the quality and consistency of the keyboard can be quantified. It can also reveal design issues, such as the larger keys being far softer to press than the main keys of the keyboard. The actuation force is measured in Centinewton (cN). Some companies use another figure, gram-force (gf). The conversion formula is 1 cN = 1.02 gf (i.e. they are about the same). A high quality keyboard should be as consistent as possible, with an average actuation force as near to the manufacturer's specs as possible and a disparity of less than ±10%. Greater differences are likely to be perceptible by users. It is worth noting that there is typically variance among keyboards, although most keyboard companies will try and maintain consistency - as with other reviews, we're testing our sample only.
The machine we use for our testing is accurate enough to provide readings with a resolution of 0.1 cN. For wider keys (e.g. Enter, Space Bar, etc.), the measurement is taking place at the center of the key, right above the switch. Note that large keys generally have a lower actuation force even if the actuation point is at the dead center of the key. This is natural, as the size and weight of the keycap reduces the required actuation force. For this reason, we do display the force required to actuate every key but we only use the results of the typical sized keys for our consistency calculations. Still, very low figures on medium sized keys, such as the Shift and Enter keys reveal design issues and can easily be perceptible by the user.
Meanwhile, regular readers who are familiar with our keyboard reviews will want to note that a few keys have been removed from our testing pattern, due to the different layout of the keyboard.
Omron’s B3K switches are clearly much different than Cherry’s MX switches and their clones. They are tactile but the bump is so subtle that it is almost impossible to notice it. Most users would actually compare the Romer-G to the Cherry MX Red switch, not to the Brown one.
The average actuation force is at 48.6 cN, slightly higher than the 45 cN rating of the switch, but the disparity over the main keys is only ± 5.75%. This indicates that Omron’s switches are of very good quality, with little inconsistencies between their products that cannot be perceived by human touch. It is worthwhile to mention that the operating force of the larger keys is similar to that of the main keys, even that of the huge Space Bar.