Sagging Voice Coils?


I was just reading a thread on AA where someone mentioned that one should rotate bass drivers to prevent the voice coils from sagging. It sounds like a problem for geriatric speakers, but is there any truth to this?
bojack

Showing 7 responses by rrog

Viridian, The surround on your Klipsch speakers is a continuation of the cone material. Also, the woofer in your speaker dictates the sensitivity of the speaker, so with 102db sensitivity the woofer cone is very light weight. It's not very likely to sag like some of the heavier materials, but if it does you know what to do.
That's nice you are an audio club. I'm not in an audio club, however, I have experienced sagging woofers. For all I know YOU might be an urban legend.
It is true that some drivers need to be rotated 180 degrees due to becoming off centered. It has to do with the weight of the driver putting pressure on the surround over a long period of time. This is less likely to happen with smaller lighter drivers than with larger heavier drivers and the surround material has a lot to do with it. For example, a 12" poly cone woofer with an inverted butal surround would most likely benefit from periodic rotation.

If your drivers need to be rotated you should be able to see a difference in the width of the surround by comparing the top to the bottom.
Viridian, Your use of the term ad hominem was inappropriate. I am sharing with this forum what I know to be true through experience for the benefit of interested parties. Just because you have not experienced this with your antique speakers does not mean it doesn't exist.
Viridian, I beg to differ. Unless I misunderstood you, I was under the impression you made it personal with your comment; because you and others in your club never experienced woofer sag that it must be a myth. Isn't that what an urban legend is? If that is the case then you were implying my explanation was BS.