(a)   No person or organization shall engage in any performance or use any electronic device in any manner so as to create a public disturbance by the operation of any sound amplification system from within a vehicle so that the sound is plainly audible at a distance of fifty feet or more feet from the vehicle.
   (b)   Definitions:
      (1)   “Sound amplification system” means any radio, tape player, compact disc player, loud speaker or other electronic device used for amplification.
      (2)   “Plainly audible” means any sound produced by a sound amplification system from within the vehicle, which clearly can be heard at a distance of fifty feet or more. Measurement standards shall be by the auditory senses, based upon direct line of sight. Words or phrases need not be discernible and bass reverberations are included. The motor vehicle may be stopped, standing, parked or moving on a street, highway, alley, parking lot or driveway.
   (c)   It is an affirmative defense to a charge under this section that the operator was not otherwise prohibited by law from operating the sound amplification system, and that any of the following apply:
      (1)   The system was being operated to request medical or vehicular assistance or to warn of a hazardous condition;
      (2)   The vehicle was an emergency or public safety vehicle;
      (3)   The vehicle was owned and operated by the City or a gas, electric, communication or refuse company; or
      (4)   The vehicle was used in authorized public activities, such as parades, fireworks, sports events, musical productions and other activities; and
      (5)   The vehicle was used for the promotion, propagation or dissemination of material protected by the First Amendment to the U.S. Constitution.
         (Ord. 21-97. Passed 4-14-97.)