Rotating a subwoofer in it's enclosure.

[hydroep]

Came across a home subwoofer review with an interesting piece of info. which could be useful to the car audio enthusiast.

Frontfiring subwoofers, on the other hand, are a little harder to position effectively in a room (though corner placement usually works pretty well) and have the technical disadvantage that their cones are sometimes so heavy they can ‘sag’ over time, which then has the effect of displacing the voicecoil in the magnetic gap, which can in turn lead to non-linearities, or even voice-coil scraping. It is for this reason that many experts recommend physically removing a subwoofer’s driver every year and rotating it by one ‘bolt-hole’ to equalise the forces. (You need to keep track of how far the driver has been rotated. After one complete revolution, you start back in the opposite direction, in order to avoid over-twisting the wires connecting the speaker to the internal amplifier.)

http://www.avhub.com.au/ProductReview.a ... viewID=130

Personally, I've never had such a problem. I usually mount the sub so that the logo is upright and leave it like that. Plus IMO the better quality car subs are more robust to withstand the additional forces (bumps, jolts) etc. encountered in the mobile environment.

However, this technique might be especially useful for cheaper subs with less wholesome motor assemblies. Regardless of build though, I suppose if you're keeping the sub for a very long period of time, it can't hurt...

[- Rovin's car audio -]

hmm...doubt if anybody even worries about this though ....

[DJ Q]

hmm...doubt if anybody even worries about this though ....

x 5,000,000

I figure manufacturers would have found a way to overcome these minor things

[Chiney]

i change subs every month

[DJ Q]

i change subs every month

[Chiney]

type r fuh sale

[hydroep]

^^^:lol:

hmm...doubt if anybody even worries about this though ....

x 5,000,000

I figure manufacturers would have found a way to overcome these minor things

Well, I guess that depends on how you define minor. Most audiophiles spend thousands on good speakers with the intention of keeping them a while. Usually, they also want to get top resale value for their gear when considering an upgrade so they'll do everything possible to keep it in top condition.

If you can easily afford to replace your equipment then it really doesn't make sense going through all that trouble...

[MonsterPower]

hmm sounds good in a weird twisted sort of logic tho

[silent_riot]

hmmmm

If the effects of gravity on the voice coil had to be "equalized", then they should rotate the sub 180 degrees instead of just one bolt hole.
If this actually happens, then rotating the sub by one bolt hole would not offset the effects of gravity, it would just shift the position of the voice coil offset, not reverse it.

And i guess if this effect actually occurs (which I really doubt), it would be more prominent on midranges and midbasses where the mechanicals are softer and built to handle less motion.

[hydroep]

Actually some guys just rotate 180 degrees after 6 years instead of the annual 1 hole rotation...

[Pirate]

instead of rotating the sub, just flip the box over...
instant 180 degrees
:-S

[DJ Q]

^da actually make sense

[hydroep]

Brilliant...

[pyromaniax]

so what if u have ur sub facing up?

[DJ Q]

then the gravitational force would be equal

[hydroep]

^^True.

But there could be other problems, similar in nature to those discussed in the threads on mounting a sub in a downward firing position...

[pyromaniax]

link to the thread plz?

[hydroep]

http://forums.trinituner.com/forums/vie ... ard+firing

http://forums.trinituner.com/forums/vie ... t=mounting