Inside the 4 Professional
Grabbing one of our many key pullers (since one is not offered with this keyboard), we do in fact find the tactile Cherry MX blue switches. These will offer fair resistance when pressed, and will give an audible click at the activation point, as well as a clack when the caps bottom out on the steel plate.
Each cap is color molded in black, so there are no paints or coatings to wear off like many other caps out there. As we mentioned, rather than printing the logos with paint, these are laser etched deeply, are easy to feel, and will last for a long time to come.
Disassembly is very simple, and only requires a few screws to be removed; none of which are hidden. This allowed us to separate the aluminum top panel from the plastic base, and as the orange arrow points to, we can see the magnets applied in the base that grab onto that footbar.
When we first got inside, we found that to remove the main PCB, and get this PCB out of the base, we had to remove some screws. These PCBs were both screwed down to solidify this design as much as possible. This PCB is where all the magic happens though; all of the controllers are here, and communication to the keys is carried over through the ribbon cable.
We removed that paper sticker from the IC that was way to the left in the last image; we found it was hiding the Nuvoton NU0123 naming of the 32-bit Cortex MCU, which is used to handle all of the traffic from the keyboard to the PC.
Flipping that PCB over, right near the volume control knob, we also find the VLI VL012-Q7 IC. This VIA chip is new to us, and rightly so, considering that this is the USB 3.0 hub controller used in this design.
Finally, we get down to the main PCB and the workmanship inside. We see very clean solder points, and no remains of flux anywhere. This can be said for both PCBs; they are some of the cleanest to date actually. Also, this and the steel plate are screwed into the chassis to help eliminate any vibrations from key clicks.
At this point we have the Das Keyboard 4 Professional all back together, and powered up for our initial testing. We can see that once the locks are activated, they are denoted with blue LEDs up by the media keys.