If you sing or play a brass instrument, the loud booming that comes from inside your head and reflects against plugs (or your fingers), called occlusion, makes

If you sing or play a brass instrument, the loud booming that comes from inside your head and reflects against plugs (or your fingers), called occlusion, makes traditional plugs unusable or actively harmful. The only solutions are to use custom molded plugs that go past the bend in your ear canal ($$$) or over-ear defenders which do not have a neutral reduction in sound across the spectrum.