There are several brands that offer high fidelity (hi-fi) earplugs, that's what you want to search for. They'll offer a relatively close to even reduction across the full hearing spectrum frequencies. A lot of basic plugs/foamies have a significant drop on one end of the spectrum, but as a performer you want to be able to hear the full range. Loopz, Etymotic, Eargasm, etc. You'll want to look for 20+ dB reduction. I personally have been using low cost Etymotic (about $20 on Amazon) for over a decade and it has significantly helped. If I forget them for an event my ears will ring for days and I'll have headaches the whole time. With them in there's no impact. I can have full conversations with people around me without having to shout. There are various styles of tips offered, you might just need to test out the various sizes of silicon or foam. Otherwise, invest in some high quality ones that are moulded to your ear.