I'll get to the noise.
But first, some science. Or maybe math? (Physics, probably?) Whatever. Science. This isn't a classroom setting, so it really doesn't matter what we call it. Anyway: let's talk decibels.
The decibel (dB) is defined as the unit that measures the intensity of a sound by comparing that sound with a given level on a logarithmic scale; it's commonly used in acoustics as a measure of sound pressure level. Here's the field version of the unit definition, because sound pressure is a field quantity (duh), and that's totally something you knew before you came to this page to read about what you thought would be hockey:
Lu01a4 = 20 log10 ( u01a4rms / u01a4ref ) dB, where u01a4ref is the standard reference sound pressure of 20 micropascals in air or 1 micropascal in water
I don't know what any of those numbers/letters/words mean, but the whole thing is pretty official-looking and effects a level of scholarliness not often found in my posts.