If the magnet provides the attraction/repellant force to the voice coil due to the electrical signal it is getting, which in turn moves the cone that creates the sounds waves, then not having a magnet or voice coil creates a speaker that relies on the pressure of another speaker to cause it to move, right?
Actually, it doesn't create a speaker.
Think of it like moving your hand back and forth in the air. Even if you could do it very fast, it will only make a little wind noise. You could change the air pressure around you hand if it moved it real fast, but that is about it. The movement of the PR is about the same.
So the stiffer the suspension of the radiator the more resistance it causes on the normal speaker,
At some frequencies yes and at others no. Increasing the stiffness will increase the Fs and thus the tuning frequency.
and the less stiff the suspension the less resistance to the normal speaker.
What it really does is lower the Fs.
So having a stiff suspension on the radiator is the same as having a smaller enclosure for the normal speaker. If you didn't have a stiff suspension then you could add weights to the radiator and do the same thing. However, and this is where I am really confused, how does adding weight affect the radiator in any position besides being face up?
Adding mass lowers the Fs and lowers the tuning, just like adding length to a port.
If it is face down and you add weight that would make it sag and I have seen some speakers that say do not mount face down.
It is true that a PR mounted vertically will tend to sag over time.
If it is mounted sideways, like mine is according to the design of the sub kit, then aren't you relying on inertia to move the cone out and the surround to pull it back in?
Inertia doesn't move it. Inertia is what it has after it is moved. And the PR works the same regardless of which way it faces, just like a port.
And wouldn't this affect the sound differently than if it were mounted face up where inertia moves it out and gravity pulls it back down?
It doesn't work that way. Inertia, in this case, is when an object maintains its velocity unless an opposing force acts on it. Gravity, like wise has no effect.
Think of it like this.
You get in the back of a pick up and stand on the open tail gate.
Now make little short bounces as fast as you can moving about 1/2" up and down. There is little effect at all on the movement of the truck. The mass of the truck is too great, the wavelengths too short.
Now take some long bounces up and down and time it with the recoil of the spring action of the truck. Now you are hitting its Fs (so to speak and for the illustration). Now you can make it move like crazy and with the same weight as before.
Make sense?
I have seen other radiators where there is a screw for you to add weight and I can't figure out how you could make a design other than a face up sub work properly using this technique. Where am I lost at??
Again, adding mass changes the Fs and changes the tuning.
For instance. If you added a ton of weight to the back of that pick up truck. Now the long strokes that you need to get it really moving as even slower. Likewise, if you removed all the weight and took the bed off of it, the gas tank out, the exhaust off and everything else out of it... Now it will bounce with much shorter strokes and more quickly. And hey, the suspension has stayed the same.
Make sense now?
