On Wed, 19 Sep 2007 10:48:36 -0000, "
wrote:

I have a subwoofer in which there is a strange noise with the speaker
as if the voice coil or the cone of the speaker is touching somewhere
so wat to do to prevent the noise . . .


Depending upon the quality of your power amplifier and/or the level at
which you have been driving it, your woofer voice coil may have been
overheated and damaged as a result. Only you will know whether this is
the case or not. Use the visual inspection and finger press technique
suggested by NC to ascertain any obvious problem, but my money is on
the voice coil being damaged. In this case the only solution is to
replace the cone/voice coil - provided that one is available for your
speaker. Usually, most respectable brand name speakers will have
spares available.