Won’t work sadly, the “counter sound” can’t be in phase in multiple locations because of delay and reflections. Headphones can do ANC because the ear is basically a single point so the mic can pick up exactly what you’re about to hear and then compensate.

Using a speaker like that would just create double the leafblower noise.

The knight, like the other vessels, is a child of the Pale King and the White Lady, likely injected / modified with Void when still in the egg.