Quick woofer seal questions (LE-10)

[Ralph856]

So not enough of a reason to take up with the shop?

[ratitifb]

Quote:
Originally Posted by Ralph856
Thanks




Could you please elaborate on this comment from yesterday? Is the excess glue serious and can it be rectified by the people who did the refoam?

It's ugly but not a serious issue.

i agree with that but this refoam job isn't correct (state of the art ). Excess of glue is equivalent of added mass on the cone and the stiffness/damping characteristics of the cone are locally modified in the glue area ...

[Ralph856]

Would that, in your estimation, be sufficient reason to ask the shop to clean the cones up at their expense?

[LRBacon]

A 'respected' company called Wembley Loudspeaker. It's the same on both drivers. Is it really bad?




One driver also buzzes when there is really strong bass. I'm hoping it's not to do with the voice coil beginning to separate from the cone. Is there any way I can take a close up photo to prove one way or the other?

I would check to make sure the surround is completely glued to the cone all the way around it. At higher volume levels it will flap in the breeze so to speak and cause a buzzing type sound. I doubt very much that the cone is separating from the voice coil.

Larry

[grumpy]

might also want to verify that the "tinsel" leads (between terminals and cone)
are routed such that they don't hit/touch the cone when large inward excursions
take place...

[Ralph856]

thanks and thanks. For some reason it's starting to distort MUCH more than before and even at quite low volume with minimal bass! The only thing that has changed (since it wasnt distorting so much) is that I turned the driver 180 degrees today. Hmmm


I'll take the driver out and have another check.

[grumpy]

sounds like a rubbing voice coil...

might start looking for a used replacement or recone-type repair if you
wish to keep the speakers, or sell them and cut your losses.

[Eaulive]

sounds like a rubbing voice coil...

might start looking for a used replacement or recone-type repair if you
wish to keep the speakers, or sell them and cut your losses.

Yes, it does sound like that.
To make sure gently push the cone by pressing on the outside of the cone, close to the surround. Theorically it should not rub, or maybe very slightly when pushed deep enough.
Do this at every 90 degrees around, if the cone rubs, it should at least rub equally from all angles. If it does not rub from an angle but rubs ALOT from the opposite angle (180 degrees) with the same pressure, it's definitely off center.

Of course if it rubs when pushed equally from around the dust cap, it's a no-brainer

[Ralph856]

Just tried it. It seems to move freely about 4/5 of the cone but for 1/5 the cone suddenly stops moving, as if there is something solid behind it.

Guess what? It's does the same thing in exactly the same place in the other cone, too.

[Eaulive]

Just tried it. It seems to move freely about 4/5 of the cone but for 1/5 the cone suddenly stops moving, as if there is something solid behind it.

Guess what? It's does the same thing in exactly the same place in the other cone, too.

You're hitting the back plate, it's normal. Actually it's not 4/5, it's 5/5 since it will never go further. Don't force it too much!
Usually you don't have to push it down so far to feel if it's rubbing.

On second thought, if it distorts more after rotating the woofer 180 degrees, it could also be the baffle surface that is not flat and/or a deformed basket that binds the coil off center.