-> DH> I'd like to see one that can deliver 130dB from 20hz-20khz, +-3dB
->
-> EF> First of all, do you know exactly how loud 130db are? It's a car
-> damned.
-> But some idiots LIKE hearing damage.  
130dB is too loud.  But if your system maxes out at 115-120dB, and you
want to run it that loud, that means you're pushing every component to
the limit.  Now, with a system capable of 130dB, 115-120dB is relatively
easy to achieve, assuring you longer lasting speakers, amplifiers and
high quality.
-> EF> Secondly: +-3dBs... You call this FLAT? 3dB is like twice as
-> loud. Let's EF> try +-1dB please!
-> Over any listening area you're suggesting a tolerance which is simply
-> not realistic.  +/- 3 dB is pretty good for most sites, and
-> particularly good in a problem environment with lots of uncontrolled
-> surfaces.
Besides that, 3dB is the accepted value for the smallest amount of
change in acoustic intensity that is audible.  A 1dB change is, for all
practical purposes, inaudible.  Also, +3dB is NOT twice as loud.  +10dB
is approximately twice as loud.
-> EF> I think we are confusing quality sound for lack of hearing
-> anything EF> else!
-> Nah.  That's after we make him a set of headphones from JBL 2445's,
-> and sweep 1.5-5 kHz into them at 50 W each.  Think he'll be able to
-> hear himself say "louder than a jackhammer" afterwards?
No thanks.  Aren't the 2445's rated at 1500w rms?  Even at 50w it's much
too loud.  I would like to have ear drums left some day.  What's the
sensitivity on the 2445's anyways?  Assuming 100dB, that would be 117dB
at 1m.  Let's see, in headphones, that would be 1/32-1/64 meters
from your ears.  Can you say (5*6dB+100dB) 130dB.  That's at 1+inches
from your ear.  At 1/2+ inches (6*6dB+100dB) that's 136dB.  Oh yeah,
that's at 1w!  Add in the 17dB and it's 147dB (or 153db)!  That's
a little loud. That's a big advantage in car audio though. Put your
mids&highs 1/4m from your years (10" approx.), and you get an
approximate 12dB increase.
-> After all, not all of us can strive for the 100 dB dynamic range by
-> pushing our environmental noise floor below 20 dBspl.
Heck, it's hard enough to do that in a recording studio.  The lowest
noise floor I've ever heard of was 15dB.  While I don't have any
notes on measurements in front of me, I'd guess that most cars
average 75-85dB noise floors.  Why are you defining the noise floor in
dBspl though? While SPL can be measured in dB, you usually see it in
Pascals. Measuring sound can get pretty confusing actually.  Can you
believe my physics teacher actually said that sound intensity was
measured in dB? Acoustical intensity is dB, while sound intensity is
w/cm^2 (I'm sure you know all this stuff) It gets to be a pain when
converting between acoustical intensity, spl, and sound intensity.  And
I thought I would never need logs!  It doesn't help that 99.9% of the
people interested in audio don't know what phons or sones are and how
they relate to SPL.
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