Originally Posted by steve71 Hearing damage at 80-90db is only caused by constant industrial noise
This is incorrect and potentially harmful information. If it wasn't for this statement I would not have replied.
In fact it's not even as loud as reference level home theater which is [edit: peaks of] 105db at the seats from all speakers and 115db at the seats from the sub.
Reference level assumes peaks (as in maximum output level) of 105 dB at seating, with a "baseline" or calibration level of 85 dB (as in dialog) at seating.
The idea of "reference level" means 85 dB SPL at the seating position with 20 dB of headroom (105 dB SPL at the seating position), and a sub that can be perceived equally as loud, hence 115 dB. I may be conflating information on the LFE channel.
It doesn't matter what causes the noise, loud is loud, and you will damage your hearing listening at absurd levels.
Current exposure charts for 85-90 dB stipulate 8 or more hours of exposure before the onset of hearing damage - the assumption with reference level listening is that the listener is exposed to a feature-length film, not an entire day of listening. At 105 dB SPL peaks, the listener should only see exposure of around 1 hour a day per current OSHA/HHS guidelines. This is unlikely to occur over the course of a feature-length film.
Some light reading:http://www.nidcd.nih.gov/health/hearing/noise.asphttp://en.wikipedia.org/wiki/Equal-loudness_contourhttp://www.osha.gov/pls/oshaweb/owad...ards&p_id=9735http://www.ce.org/Press/CEA_Pubs/2948.asphttp://www.listentoyourbuds.org/learn/http://www.avsforum.com/avs-vb/showthread.php?t=1091463http://www.tongfamily.com/archives/2...ference-level/http://forums.soundandvisionmag.com/...eference-level
So no, don't kid yourself that you cannot destroy your ears listening to movies and music at high volumes - 80-90 dB is in the realm of "uncomfortable" for most people, and can cause hearing damage with long term exposure; anything triple digit is absolutely going to cause hearing damage, it's just a question of time.