I think you might be conflating sound pressure (amplitude) and wavelength? Frequency is kind of like the speed of a wave yes, but it's not a product of the sound pressure at all. They're independent. If you haven't heard of sengpiel audio I highly recommend. He explained some of these things pretty well. I use the site for looking up acoustic calculations a lot.

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http://www.sengpielaudio.com/calculator-wavegraphs.htm