# Sound pressure level and sound intensity level

1. Oct 15, 2007

### hanson

Hi all.
A very simple question: what is the difference between sound pressure level and sound intensity level?
It seems to me that sound presssure level also measure the "energy" since it is p^2, which shall be related to energy...
If it is so, it seems that sound pressure level shall be the same as sound intensity level, isn't it?
$$\overrightarrow{I}=\frac{1}{T}\int_{0}^{T} p \overrightarrow{u} dt = \frac{1}{2}Re\left[p \overrightarrow{u}\right]$$