Curiosity would be testing whether your sound impressions hold true when all senses but your ears have been truly silenced.
This is done via level matching and double blind testing.
What you're doing, which is blindly trusting yourself to be immune to bias, despite decades of science and research proving the opposite, is not only ignorant but also plays right into the hands of fraudsters who will, when given the chance, sell you a wooden "grounding" box with dirt inside for a couple grand and will make you "hear" its miraculous effects by exploiting that very same ignorance.
They will bias you into perceiving nonexistent improvements and you'll be none the wiser. Because how could your ears ever lie to you?