Sounds less than 75 dB have no significant effect on our hearing.
Exposure to sounds above 85 dB causes short term hearing losses called temporary threshold shifts. If this occurs, your ear becomes less sensitive, and sounds seem quieter than normal. After some time, normal hearing returns.
Repeated exposure to sounds that cause temporary threshold shifts results in permanent damage to the ear in the form of a permanent threshold shift . The ear loses sensitivity in the frequencies 3,000 Hz through 6,000 Hz, resulting in a "notch" in the hearing range. Time of exposure is important, the louder the sound, the less exposure time before permanent damage sets in.
Exposure to sounds above 85 dB causes short term hearing losses called temporary threshold shifts. If this occurs, your ear becomes less sensitive, and sounds seem quieter than normal. After some time, normal hearing returns.
Repeated exposure to sounds that cause temporary threshold shifts results in permanent damage to the ear in the form of a permanent threshold shift . The ear loses sensitivity in the frequencies 3,000 Hz through 6,000 Hz, resulting in a "notch" in the hearing range. Time of exposure is important, the louder the sound, the less exposure time before permanent damage sets in.
According to OSHA, the exposure time limits are: (these are A-weighted, most home theater measurements are made with C weighting, which typically gives higer readings for broad spectrum measurements).
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If you like to crank it on up during the "good parts" to really feel the action. Look at your results from the Peak SPL Calculator compared with the OSHA guidelines. Most moderate HT systems are capable of 102 to 107 dB peaks at a decent (10+ feet) listening position, at these peak levels the normal dialog is going to be at least 85-90dB, within the range where permanent hearing loss can occur.
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