And so it came to pass, on 16-07-96 09:48,
   that Tyler Smith spake unto Gordon Gilbert:
 TS> ΔΝώΝΔ We overheard Gordon Gilbert complain to  Matt Ion ΔΝώΝΔ
GG>>      Not quite?  Do you realize how *loud* 140dB is and you say
GG>> *not quite* !?!?  Why 140dB?  Is that the level your ear drums
GG>> instantly explode at or something?  Human hearing is incapable of
GG>> even realizing dynamic levels beyond 120dB (it just becomes
GG>> distortion 
 TS> i agree completly with gordon...the db scale is compounded sound,
 TS> which many people do not realize...they listen to their radios at
 TS> 20 thinking, "oh this is nothing..." then they crank it up to 40
 TS> and say, "damn." and they find out that it is quite a bit lounder
 TS> than twice as loud as 20db....
Volume knobs are NEVER labelled in "dB SPL".  MOST aren't even labelled in dB 
at all -- they just mark both ends of the scale, divide it up into even 
segments, and slap meaningless numbers on those segments.
Every 3dB represents a doubling or halving of power, but a 3dB change is 
barely detectable by the human ear.  A change of 10dB represents a 10-fold 
increase or decrease in power, but the human ear will perceive a 10dB boost 
as being only twice as loud.
BTW, 20dB is right around the threshold of average hearing -- in other words, 
almost too quiet to be heard.  40dB is 100 times as loud, but will seem only 
four times as loud.
 TS> therefore, 140db is incredibly loud...and on another note...i just
 TS> read in a memo that the db was broken in sub-woofer audio...this
 TS> guy had 8, yes EIGHT 15's with 6500 watts...you can bet he did some
 TS> damage to his eardrums when the things hit twice at 160db...just a
 TS> little tidbit of information you'll never use...      
If he was inside the vehicle when the subs hit 160dB, he'd be dead.  The 
vibrations would have stopped his heart instantly, or sufficiently altered 
its rhythm to put him into cardiac arrest, and quite possibly have crushed 
his ribcage.
The last time I checked (which admittedly was a couple years ago), the SPL 
record for car audio was held by Mark Fukada's Chevy Blazer, hitting just 
over 157dB.
IKEA ... Swedish for "particle board."
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