Thock vs. clack
Compare the character, not just the volume.
Thock and clack are useful enthusiast shorthand, but keyboard sound is more than one label. Clack Lab combines frequency balance, decay, high-frequency ratio, level, and consistency to make before-and-after tests easier to inspect.
Thock
Often described as deeper or rounder, with more energy in lower frequencies and a controlled decay. The exact result depends on the board, room, and recording setup.
Clack
Often described as sharper or brighter, with more high-frequency presence. A brighter result is not automatically worse; it depends on the build and the listener.