Each county, city, etc has different zones - so it depends on which city you live in and where in the city.
For example - Santa Rosa, CA.
Scroll down the file - page 5 etc.
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And here is the City of Santa Rosa, CA noise ordinance law ~
17-16.070 Radios, television sets and similar devices.
(A) Use Restricted. It is unlawful for any person within any residential zone of the City to use or operate any radio receiving set, musical instrument, phonograph, television set or other machine or device for the producing or reproducing of sound in such a manner as to disturb the peace, quiet and comfort of neighboring residents or any reasonable person of normal sensitiveness residing in the area.
(B) Prima Facie Violation. Any noise level exceeding the ambient base level at the property line of any property (or, if a condominium or apartment house, within any adjoining apartment) by more than five decibels shall be deemed to be prima facie evidence of a violation of this section. (Prior code § 27.15)
PS - SRPD have meters, I'm guessing Oakland PD does too.