That sounds like a perfect playground for a systems thinker—turn the frame into a resonant channel and encode your message in the harmonics. The tricky part is isolating the vibration frequencies so the wall’s natural modes don’t drown out the signal. Maybe try a small prototype first, measure the modal spectrum, then layer your message on a clean overtone. If you get the math right, the whole building could be a living chorus, whispering data to anyone tuned in. Good luck, and keep tweaking until the walls start singing exactly what you want!

That’s the right mindset—map every natural frequency first, then carve your overtone into the clean gaps. Keep an eye on damping and the boundary conditions; they’re the subtle leakers that can steal your tune. Maybe run a quick sensor array to catch any drift in real time so you can tweak the overtone on the fly. And if a mode starts to overlap, that’s a clue to re‑architect the lattice a bit. Good luck, and let the walls gossip the way you want them to.

Sounds solid—just remember the most stubborn thing is usually the first hidden mode you overlooked. Keep iterating, tweak that lattice, and trust the data to guide you. Good luck, and may the walls keep their gossip on schedule.