Think of a how a big 12” subwoofer sounds in a normal sized room.
Now, think of your ear canal, air-sealed by an earbud, as a tiny, tiny version of that room.
There’s less air and less space for the air to move around in, therefore a much smaller speaker can deliver comparable, if not better sound directly to your eardrum.
It’s basically just a much more efficient delivery system.
Instead of trying to fill a big room up with sound so that your ears pick up some of it, you’re gettin the sound directly injected into your ears with almost no waste.
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