For reference, I have used equipment to tune home theaters to flat frequency responses, and designed speaker crossovers. Spreadsheets are fun, and sound is math.

Like the other commenter recoed: Loops www.loopearplugs.com.

The loop is tuned for specific frequencies, and it actually works. My partner also uses them on job sites, and the soft ones are great for sleeping. I typically use the ones for loud places that help you hear voices.

Regardless of where you live, you can buy them in your currency on Amazon if you can’t find a direct purchase: www.amazon.com/s?k=loop+earplugs&crid=2GUCLFWL47X…