Thank you all for the concern for my well being. Outmost appreciated. I do not listen to 150dB music yet as i need more power and bigger speakers.
Now back to next question. With fairly large main speakers, do I also need a large center channel or does it not matter to much? Currently I have none so i think that’s next
120dB USED TO be called 'threshold of pain', now that's called 'threshold of feeling'- threshold of pain has increased to 130dB. When an audio system is involved, a 10dB increase in SPL comes from increasing power by 10 times, assuming all other things are the same. 150dB is barely survivable and definitely not if exposure is long-term. It also means the power (again, all other things are equal) has increased by 100 times over 130dB, 1000 times more than what was used to achieve 120dB. Sound pressure isn't measured on a linear scale, nor do we hear on a linear scale, so increases by a factor of 10 are very relavant to our perception of loudness.
Loudness is one thing, intensity is another- what we hear can sound loud when it's actually not, but the intensity makes us believe it is loud because of our increased sensitivity centered in the 3KHz-4KHz range, but we're also more sensitive in the range from 1KHz-5KHz, compared to the ranges above and below. The chart shows typical human hearing sensitivity (only one of many, with varying results- I'm only showing it to make a point)-
This image is a CDC noise exposure chart- you should note that it doesn't show anything above 100dBA and that's because there is no amount of time for exposure to that SPL which is safe for a person's hearing. Now, increase it to 150dB and the damage occurs immediately. It's permanent, too.