Mechanical Keyboard Switch Testing Explained

Issue Concerning Rebound

Although the texture analyzer does measure the switch rebound, we discovered that there is an issue with our testing method that throws off the measurement slightly.

Note that in our charts, at the end of the key travel there’s a sharp upward spike in the force measurement. This spike is where the probe found the end of the key travel and encountered resistance. (Because of this spike, we can look at the raw data and determine the end point of each switch’s key travel.)

Bear in mind that switches are made of plastic, which is of course a material that compresses, and further, the probe can apply high amounts of force and can flex even a sturdy metal backplate. Therefore, the spiked portion of the line measures the force the probe applied and the distance the probe traveled, not necessarily the force and distance of the switch, because the probe will continue to depress (and compress) the switch far beyond what human fingers can.

When the probe retracts, the force drops down from that spike. By looking at where the spike ends, we can also find where the rebound of each switch begins, and the texture analyzer measures the force and distance of the rebound.

For individual switch measurements, this is not an issue. In the graphs, you can plainly see where the travel ends (at the beginning of the spike) and where the rebound begins (at the end of the spike). Looking at the raw data, we can further pinpoint the end of the travel and the beginning of the rebound.

However, when we combine all the switch data together to look for a median, we encountered two problems, because we were comparing raw data line-by-line.

Because the ends of the travel are all slightly different switch-to-switch, and the amount of force/distance during the spike was slightly different switch-to-switch, the beginning of the rebound switch-to-switch didn’t line up well at all.

This first problem is easily solved by identifying the ends of the travel for each switch and the beginning of the rebounds of each switch and aligning them. However, this method leaves some small gaps in the data that we had to account for.

The second problem is that, upon close examination of our raw data, we discovered that the distance measurements, switch-to-switch, no longer aligned precisely once the switches begin their rebounds.

For example, below is a spreadsheet showing measurements of multiple switches on the keypress - note that the distance is identical across all cells, and thus the distances between each measurement are uniform:

Swipe to scroll horizontally
Row[Name of keyboard and key X][Name of keyboard and key X][Name of keyboard and key Y][Name of keyboard and key Y][Name of keyboard and key Z][Name of keyboard and key Z]
Row 0 - Cell 0 Force (g)Distance (mm)Force (g)Distance (mm)Force (g)Distance (mm)
153.92.83854.92.83855.42.838
254.42.84855.62.84854.82.848
354.92.858552.85854.42.858
454.62.86854.82.86854.52.868
554.22.87855.12.87855.12.878
654.92.88856.12.88854.62.888
7552.89855.72.89854.12.898

But during the rebound, those same switches give us data like this (below). Note that some of the distances are different across the cells, and also the distances between each measurement are not uniform:

Swipe to scroll horizontally
Row[Name of keyboard and key X][Name of keyboard and key X][Name of keyboard and key Y][Name of keyboard and key Y][Name of keyboard and key Z][Name of keyboard and key Z]
Row 0 - Cell 0 Force (g)Distance (mm)Force (g)Distance (mm)Force (g)Distance (mm)
152.53.958533.87146.93.727
249.73.92851.33.82750.83.677
3483.89249.43.77754.43.627
446.53.848513.72754.23.577
544.23.798553.67752.93.527
645.43.74856.13.627543.477
749.13.69856.53.577543.427

Were the deltas between each distance measurement still uniform, our solution to the first problem (manually aligning the beginning of each switch’s rebound) would solve this second problem. But because the deltas are not uniform, it cannot.

Therefore, in looking at the median performance of a given set of switches, we have had to sacrifice a small amount of precision (artificially filling in gaps in measurements) for the sake of accuracy (better showing the median of the ends points and of the rebound beginnings). Further, because of our current testing procedure, the data showing the median of the full rebound is also accurate switch-to-switch but not precise as a true median.

Again, none of the above affects the measurements and graphs of the individual switches, including the rebound. However, because we use the median of all the switches as a baseline from which to evaluate tolerances and spot outliers, this means that we will refrain from making any evaluative determinations about switch rebound performance.

Further, these differences, we should point out, are fairly minute - often a matter of less than a tenth of a millimeter - but even so, we want to be careful about making judgments without precise, objective measurements.

Still, our rebound data is instructive in some ways. For example, it shows the force curve of the rebound of each switch, and that’s informative. And if there are any aberrations in the force curve of the rebound of any particular switch, such as a particularly ugly dip or spike, that’s also useful data.

MORE: Best Deals

MORE: All Keyboard Content

• hunshiki
As in for example a Brown switch is how hard to press at first, and how it degrades.

Because I used Blue and Brown switches, and they both get mushy after a few years of use. Brown was like 1 year, Blue was ~2-3 before getting mushy. They both just lose that tactile bump feel to them.

The Brown cap kb was a Corsair Strife RGB, the Blue was a Razer BlackWidow. Cherry cap, original, older model.

Of course this test could only work with tactile ones as Reds don't change with time. For example Reds simply bottom out and that's the only feel you can get out of them.
• raulinbonn
I'm looking forward to measurements and comparisons between mechanical Cherry Blue switches vs. the recent hybrid from Razer, the so called "mechamembrane" Ornata, which I find to be excellent and pretty much peerless for typing purposes
• scolaner
As in for example a Brown switch is how hard to press at first, and how it degrades.

Because I used Blue and Brown switches, and they both get mushy after a few years of use. Brown was like 1 year, Blue was ~2-3 before getting mushy. They both just lose that tactile bump feel to them.

The Brown cap kb was a Corsair Strife RGB, the Blue was a Razer BlackWidow. Cherry cap, original, older model.

Of course this test could only work with tactile ones as Reds don't change with time. For example Reds simply bottom out and that's the only feel you can get out of them.

Well yes, so would we. :) As we stated, we just don't have the capability to test that at this time. If you have suggestions for tools we could use to do so (that aren't super-expensive pieces of factory equipment), please let us know!
• cats_Paw
I am quite sure anyone who ever used a mechanical keyboard can confirm that the 50 million clicks is a myth.
I have used 3 keyboards in 5 years (two of them are dead now) and I certainly did not click 50 million times on the same key.

But ofc, who is gonna bother to confirm this?
Id say 1-3 Million is a bit more realistic.
• munted
Is a standard office membrane keyboard going to be tested for comparison? I've used Cherry Blue and Brown switches and found both of them quite tiring to type on although I didn't use them for very long, I've always wondered how much effort a mechanical keyboard is compared to a membrane.
• bettsar
I'd love to see an article that compares 1 or 2 cheap rubber dome keyboards to some with mechanical switches. Texture, noise, force. It would be interesting, and potentially helpful in understanding whether I should spring for a nice mechanical keyboard or not.
• scolaner
I'd love to see an article that compares 1 or 2 cheap rubber dome keyboards to some with mechanical switches. Texture, noise, force. It would be interesting, and potentially helpful in understanding whether I should spring for a nice mechanical keyboard or not.

We do have data on that. We have a ton of content coming based on all our testing, but that's one I hope to tackle when I have the chance.
• bgunner
Roughly how long will it be before we start seeing articles using this type of data?
• scolaner
Roughly how long will it be before we start seeing articles using this type of data?

POOF, your wish is granted :D : http://www.tomshardware.com/reviews/patriot-viper-v760-mechanical-gaming-keyboard,4798.html