Most of the music we love doesn't go very low in frequency.

The lowest note on a standard bass guitar is around 41Hz. A kick drum fundamental sits between 50 and 100Hz depending on the drum and tuning. A concert grand piano's lowest string produces its fundamental at about 27Hz. Pipe organ is the real exception — the largest pipes can reach below 20Hz — but almost no recordings capture that.

In practice, most music lives well above 30Hz. A system that reaches cleanly to 35Hz will handle the vast majority of recordings without missing anything audible. So why do so many of us obsess over the last octave?

Because bass isn't only heard. It's felt.

Below about 40Hz, the ear becomes less efficient at processing pitch, but the rest of your body takes over. Deep bass creates pressure changes — you feel it in your chest, your seat, the air around you. That physical sensation is part of what makes a live performance feel fundamentally different from a recording. A great concert hall doesn't just fill your ears. It fills the space you're sitting in. Getting some fraction of that into a home system is what deep bass extension is actually about.

The music doesn't always reach that low.

But when it does, you'll want to know.