Just use corrugated cardboard and with longer sine waves, duh!

I am not an audio engineer but you might have a point in that the longer low sound waves would be harder to block.

Where my audiophiles at? We need a sound check on low frequency blocking.

Edit:
Found an article on a crypto mining facility mitigating noise issues.

https://noisemonitoringservices.com/data-center-noise-control/