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Paul Vina
 
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Default Facing subs towards driver or away

If you read Nousaine's posts he tells you. There IS a change in your
system, he and Eddie disagree as to what frequencies are affected.


Paul Vina




"Luke Hague" wrote in message
...
I guess my big question, which Eddie seems to be the only one who can
answer, is why DOES it make a difference when you turn the box around? and
when I mean turn the box around, I DON'T mean change anything else.

"Nousaine" wrote in message
...
Mark Zarella
wrote:

But Eddie and the woofer-direction folks aren't talking 90 Hz.

What gives you that impression?


Because that's not what he talks about.


But I'll agree
that many people will interpret changes at 100-200 Hz as "Bass"

effects.

As they should be. Furthermore, there's quite a bit of information
under "100-200Hz" yet above 20Hz. Wouldn't you agree?


Sure but most of that, generally below 60 Hz or so depending on vehicle

size,
is happening in the pressure zone where woofer location and direction

are
irrelevant.


What is interesting is that with the woofer facing the listener it's

quite
likely that there will be significantly more low-midrange output.

This
can
either be an advantage or a problem, depending.

But the argument in this thread is that simply facing the woofer

toward
the
rear of the car delivers more bass.

Not the way it's been stated by Eddie. Eddie has simply pointed out
that it provides a difference, not that it's necessarily better. He's
mentioned that people TEND to like it the other way, and he's described
the source of the difference.


No he doesn't.He never mentions any frequency other than 60 Hz. He has

shown no
understanding of the physics involved and the true acoustical nature of

what's
happening.

His description is straightforward and
obeys the laws of physics, yet he's never gone into the specifics of

the
effects on the spectral response.


It doesn't obey the laws of physics at all. The 'effect' he describes is

not a
standing wave effect at all and it doesn't occur at 60 Hz as stated in

his
example with the physical distances stated.

The 'effect' he describes is best described as a single wall reflection
interference notch or a floor bounce with a tower speaker where the

effect
with
a 60 Hz signal will occur at.150-300 Hz.


It can only do that when you consider
upper-bass and lower midrange(usually 80 hz and above) as the key

elements.
Depending on the intended woofer operating range this may or may not

be
important.

It's almost always important.

But the general population seems to simply classify any change in

sound
as
more/better "bass" when it's not.

I think it's useful to break down these Urban Legends into component
factors
and focus on what's really happening acoustically.

Yes, it's worth an in-depth description. I think Eddie's webpage
provides a general description, but it's hardly a comprehensive one.
His website is geared towards users with a certain level of expertise,
and I suggest that someone further describes the effect. Preferably,
someone who's actually made the measurements. But to come in and say
that the effect doesn't exist flies in the face of the common
observations made by just about everyone that's installed a subwoofer.


I've fully described what actually happens on this newsgroup. I've also

done
the experiment a number of times and I've replicated the Eddie example

outside
with a single wall reflection with a 12-inch woofer in a small sealed
enclosure.

In his example one can see an interference notch with his suggested

3-feet
distance that occurs at 280 Hz. Other than that the basic "difference"

between
the woofer faced directly into the wall compared to the same woofer

facing
away
from the wall was approximately 9-dB more output above 400 Hz.

I've never said that no effect occurs. I've simply described what

actually
happens and at what frequency it occurs.

Eddie's description is very misleading and he seemingly hasn't actually

ever
done the measurements or he would know that his description is

incorrect.

I'm sending an e-mail to you with "woofer direction" measurments

actually
taken
in a hatchback car where the response and Max SPL capability are

graphically
described.