Opening up Excalibur is a simple task. After removing the 7 visible screws, it all comes apart quite easily. I have to say, I like when a manufacturer makes it simple to get inside. It shows trust in its audience, as well as confidence in the product itself.
Excalibur Spectrum has an exceptional interior build quality. The PCB is one of the cleanest I've seen on mechanical keyboards, with little to no excess soldering whatsoever.
The Kailh RED switches are fixed onto a very thick white steel plate, which most assuredly adds most of the heft behind the mech.
You will find 1x AMS1117 voltage regulator on the PCB back (and one on the front) with 1A output current, and a fixed voltage of 3.3V.
The brain of the keyboard is a 32-bit ARM Cortex-M0 NXP LPC11E14F/401 micro-controller with 32KB flash and 10Kb SRAM.