energy/frequency relation in quantum waves

[Ian]

I read this remark on a post in the classical physics section.

"Sound waves, unlike quantum waves, don't have frequency proportional to energy".

Can anyone expand on this for me?
Why is the frequency in quantum waves related to the wave energy?

Thanks,
Ian.

[arivero]

It is the primitive postulate. Plank constant, which has units [h]=[p][x]=[E][t] is used to relate energy and frequency, and also momentum and wavelength.

[nightlight]

Originally posted by Ian
I read this remark on a post in the classical physics section.

"Sound waves, unlike quantum waves, don't have frequency proportional to energy".

Can anyone expand on this for me?
Why is the frequency in quantum waves related to the wave energy?
Ian.
Energy dependens on frequency in many periodic classical systems. Consider an ellastic ball bouncing between two walls - the ball energy will grow with the square of the bounce-cycle frequency.