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"Luke Hague" wrote:

You just keep referring to your test which I'm sure came out as true,
because of you're test environment, but for you to prove you're theory you
should try it in multiple vehicles.
What was the vehicle you were using to test this on?

Corvette;but what difference should that make. Eddie's web-site uses NO car.

Because space is
what is the biggest factor in subwoofer direction, I may not be a
professional at car installation, but it doesn't take an expert to
understand that sound wave can be cancelled by two of the same sound waves
colliding, this can be show in a simple physics problem, such as force.
When two object traveling at the same speed, and that have the same mass,
collide, they cancel eachother out, meaning neither object moves.

Really? well how does the force get distributed and/or disappated? 2 vehicles
traveling at 50 mph in a head-on will simply stop and nothing else will happen?

Of course, you aren't but that's what you said.

What
happens, as Eddie has explained on his, in where he used test equipment
(like you) and in an average everyday vehicle, is that the back of the box
produces the same waves as the front of the box, when these waves collide,
they cancel out.

So if you put in a 60 Hz tone and they cancel out and you get no sound? If
that's true then why do you need a wall?

It's a very simple theory, and the only way it can be
proven is by testing. And in such I have, in my own vehicle, as I said
before, I changed NOTHING except the direction of my box.

I hear this all the time fromothers but every time I investigate i find that
other factors have not been controlled or documented.

As far as bias listening as you put it, I can't really object, except
only to remind you that I've done this many times in the same car, turning
the box back to the front, and then to the rear again, and each time I can
hear a greater amount of bass. I don't really understand how you can sit
there, and tell me that I am wrong when I know for a fact it's made a huge
difference. Perhaps it's something else that has occurred, but I know for a
FACT that the bass is greater with the box facing the rear.

Well then how come that doesn't occur in my car and the others I've used?

This theory can also apply to home theater, or sound systems, in fact it
could be proven to you easier here than in a car. If you take the sub
woofer for the speaker system, and it has to be just the sub and it has to
be loud, take that sub and play a real low tone through it, then face it
against the wall, now move it back and forth against the wall, not like a
couple of inches either, I'm talking feet. You WILL notice a difference.
This is attributed to that simple physics problem that you really can
dispute.

Home Theater is my specialty. Yes if you move your subwoofer away from a wall
or out of the corner response does change in the range of 30-300 Hz in the
typically sized listening room. That's because any other location, other than a
corner will fail to excite some room modes and put holes in the sound pressure.

My point is that in a smaller space, like a car, that inflection point is
raised by roughly an octave to 60-600 Hz.

In either space, room or car, below the lowest axial mode the speaker (if it
has adequate displacement) directly pressurizes the space. There are no modes
(standing waves) below this frequency. What happens with the "Eddie Effect" as
described on his web-site is that a single wall replection can cause a response
cancellation BUT NOT at or below the pressure zone.

In my experiment that occured at 188 Hz and with the woofer facing the rear of
the vehicle. Boundary cancellation is well known and has been for years. But it
doesn't happen at the excitation frequency.