@King:
In that case, his ability would be to cancel the perception itself instead of the waves.
That or his ability only works selectively. Not all vibrations are soundwaves.
I thought about the first opinion, but I went and checked. I looked at the first time he used his ability and created a sound proof field. If he were cancelling our perception of sound then he'd have to be surrounding everything with his ability for it to work. That's not the case.
He can cancel sound originating within his barrier from beings reaching outside of it.
Rocinante himself states that he's stopping the sound itself.
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@RamistaR:
You remind us that, then you explain that BB creates seismic waves in air. Logic ?
The Gura Gura doesn't create seismic waves specifically. If it travels through the air then, by definition, it's not a seismic wave.
In the real world by the way, you can't protect a building from seism by making it soundproof.
How could you stop the shaking of the Earth with something that has nothing to do with that?
What does this have to do with what I'm saying?
@Basslion:
Oh but they do share the same properties, they are waves/vibrations it's the frequency that it's different.
Rocinante ate the Nagi Nagi devil fruit and he's a soundless man as he himself said. That means he can filter out
every frequence/vibration within the human's acoustic spectrum, namely 20Hz to 20Khz.
A seismic vibration isn't though something limited to a spectrum as our hearing. You can't just filter out every possible frequency
that the vibration consists of.
Ok then. Thanks for the lesson.