Re: Speaker sensitivity and fs in multiples.

On 1 Dec 2003 11:57:39 -0800, [EMAIL PROTECTED] (Bob-Stanton)
wrote:


>To say: "You cannot sum individual powers", is a violation of the law
>of conservation of energy.
>

A serious charge. . .


>Another fundamental law a physics is Energy = Force * Distance. If
>each of four drivers in an array is pushing the air with half the
>force, for half the distance, each puts out 1/4 the energy.  The total
>power output of four will be only the same as a single driver.

You are not pushing air with half the force you are pushing the
mass/stiffnes/damping of the driver with half the force. On the output
side of the driver the work is volume * pressure. Each driver sees its
own pressure plus the pressure of three more drivers. Each driver does
four times  the work on the air that it would do if it saw only its
own pressure. This is not a "violation of the law of conservation of
energy"  since it bears little relationship to the electrical input
power which only increases very slightly due the negligible increase
in load.