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Don Pearce[_3_] Don Pearce[_3_] is offline
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Default How do sound decibels add together?

On Tue, 2 Sep 2014 21:09:02 +0000 (UTC), Jeff Henig
wrote:

Don Pearce wrote:
On Tue, 2 Sep 2014 20:23:51 +0000 (UTC), Jeff Henig
wrote:

Don Pearce wrote:
On 2 Sep 2014 14:39:09 -0400, (Scott Dorsey) wrote:

Don Pearce wrote:

So...loudness is power based, logarithmic. A stadium of 50,000 cheering
people generates power, which increases the loudness, with some
attenuation depending on phase, and is not 50,000 X the loudness of 1
person cheering.

And bear in mind that most of those 50,000 are a long way from you.
Only the nearest twenty or so people contribute in meaningful way to
the loudness you hear. The rest just add the background sussuration.

In an open stadium this is definitely the case; you can think of the top
of the stadium as being infinitely absorptive. Sound just goes up and keeps
on going. But in a closed reverberant basketball court it's not!
--scott

We don't bother with basketball over here, but a large public swimming
pool certainly proves this. Why do people insist on screaming when
they swim?

d

Maybe you should stop throwing Babe Ruth bars into the pool, Don.

(One of my fave movie pranks, BTW. Caddy Shack was a classic.)


Okay, not seen that movie, but | looked up Babe Ruth bars - couldn't
find them. But I did find Baby Ruth bars, and even before I realised
what the swimming pool prank must have been, I got what they looked
like.

What kind of a mind do I have?

d


Here's your clip. Heh...

http://youtu.be/TPxiXGr9nFM


Yup, I wrote exactly that scene in my head. Somebody had to eat it at
the end.

d