in my lexus the rear deck is all metal and i am up firing my subs with the magnets out of the box, i was wondering if it would hurt the sub if it were to touch the metel of the rear deck, since my box isnt mounted and i dont plan on mounting it
This is a good question.. I know that a magnet touching the wood of a box, in most cases, wont necessarily 'hurt' a sub..(or speaker)..other than ugly rattling/vibrations..
But with metal.. A magnet only has so much strength, (demonstratable by seeing how much metal a magnet can hold before it starts to simply fall off..) I'd honestly like to know the answer to this question too.. Wont even pretend I know if it'd cause the magnet to be weaker due to the foreign metal in close proximity , or even if it did have that cause - if it'd be significant enough to the point where it'd even make a difference...?
Sure. There is no electrical conduction going through the motor/bottom of the sub. The magnet won't do anything to the metal, and it isn't going to 'magnetize' itself off the sub.
Though, I would suggest putting some type of material between the sub and metal such as a piece of rubber, cloth, dynamat etc. so you don't scratch up the metal on the sub or lexus.
If you're worried about the box and subs slamming up against the metal, that's another story, I don't know what subs you have, but it's probably not the brightest idea as it would potentially compromise the integrity of the sub's basket.
I'm not sure of how applicable this is to a subwoofer magnet, but because permanent magnets produce fields through the orientation of the electron orbits and spins of the atoms in the magnet, if it is hit repeatedly, it will misalign those fields and the magnet will become weaker.
Is the trunk carpeted? You could probably just put industrial velcro strips on the bottom of the box to prevent it from sliding around.