dlr said:
the important part there is more kinetic energy?
In some cases down at the atomic level.
But you can apply a force, not move the object, and no work is done. When the force moves the object you have work = energy
The force is needed to do the work, but the resulting work (energy) is the metric which we need to consider -- how much energy is injected into the panel.
It is VERY relevant.
dave
Let's try this again.
The drivers cone is pushed forward by the voice coil. Forward motion of the cone acts on the driver frame to push this back. Newton's third law of motion. Clear? Picture recoil of a rifle - bullet is fired forward, gun goes backwards.
The further the cone goes forward, the more the driver frame will tend to go back. Since you need longer excursion at lower frequencies to produce the same spl, this results in further cone travel and more rearward driver motion in reaction to it.
Obvious to me that at the higher frequencies, where large cone excursion is not needed to achieve higher spl levels, there will be less reactionary motion.
The last time I used words like "force" and "energy" and these just confused a few, so I carefully avoided them here.
The drivers cone is pushed forward by the voice coil. Forward motion of the cone acts on the driver frame to push this back. Newton's third law of motion. Clear? Picture recoil of a rifle - bullet is fired forward, gun goes backwards.
The further the cone goes forward, the more the driver frame will tend to go back. Since you need longer excursion at lower frequencies to produce the same spl, this results in further cone travel and more rearward driver motion in reaction to it.
Obvious to me that at the higher frequencies, where large cone excursion is not needed to achieve higher spl levels, there will be less reactionary motion.
The last time I used words like "force" and "energy" and these just confused a few, so I carefully avoided them here.
ShinOBIWAN said:
..and with that:
http://gizmodo.com/383585/darth-vader-given-arrest-warrant-pleads-guilty-to-assault
The Youtube BBC News skit/video is quite funny.
There is either misunderstanding of the physics here or more likely confused wording.MJL21193 said:
The displacement of the driver (frame) depends on the force and the stiffness or mass of the box*. At a frequency where the box is rigid and, because it is massive, barely moves, there is little energy transferred to it (force times displacement). At a frequency where it is softer (at a resonance) the displacement is more, and more energy is transferred for the same force.
You can feel that happening if you apply a swept sine and feel the baffle. Most energy is transferred to your fingers at resonances of the baffle (or of the speaker rocking on its support).
*In simplified form: the force (F) leads to a compression (x) of a massive box acording to the effective stiffness (k) as a function of frequency (think of x = F/k) , and to an acceleration (a=(2*pi*f)^2) of a stiff box according to its mass (a=F/m). In many cases the motion due to the flexing of the box will exceed that due to recoil at box resonances.
Pick your own force spectrum to put in (either real music or the models already mentioned).
Ken
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