The human ear responds more to frequencies between 500 Hz and 8 kHz and is less sensitive to very low-pitch or high-pitch noises. The frequency weightings used in sound level meters are often related to the response of the human ear, to ensure that the meter is measuring pretty much what you actually hear. It is extremely important that sound level measurements are made using the correct frequency weighting - usually A-weighting.
'Bonanza,' 'Trapper John, M.D.' star Pernell Roberts dies. Pernell Roberts portrayed Dr. John McIntyre on Trapper John, M.D..
(born February 10, 1991) is an American actress and musician who portrays Madison Montgomery in Coven and Maggie Esmerelda in Freak Show. Emma Roberts rose to fame during her stint on Nickelodeon where she played Addie Singer in the show Unfabulous. After her starring role on that hit Nick show, she had roles in many pre-teen and young adult movies including Nancy Drew, Aquamarine, and Spymate.