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Speaker cone fault?

Discussion in 'Amps and Cabs [BG]' started by Cosmo_Smallpiece, Jan 20, 2005.


  1. I wondered if anyone had ever heard of an instance of the paper cone of a speaker coming apart from the surround where the two are bonded.
     
  2. Finger Blister

    Finger Blister

    Jul 8, 2003
    Yup.

    Over over excursion causes stressed surrounds (Overdriving).
    First they crease, then they rip.

    Overexcursion occurs when a speakers is amplified to move farther than it is mechanically capable of. For example, if 1000W rms moves a speaker 2 inches, and that speaker is designed to move a maximum of 1 inch, it will likely fail.

    Which sometimes has to do with Power Handling.
    Power Handling: The wattage level that a driver can handle without sustaining damage due to over-heating the voice coil or over-extending the cone excursion.

    Most common with LF's.
     
  3. Is it common then? Wouldn't the voice coil burn out first?
     
  4. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    The voice coil would NOT necessarily burn out first. This is the problem with the Eminence Delta 10 driver, it has such a short excursion rating that it is generally unsuitable for bass guitar application. With the Delta 10, odds are you will exceed its excursion limits WAY before you will ever fry the voice coil.
     
  5. No I'm probably asking the wrong question.

    The reason I ask is that I'm selling a Boogie roadready and a guy who looked at it noticed some yellow discolouration in that area - actually outside of the bond - but he was concerned about it.

    To me it just looks like a build up of crud and most of it cleaned off but I'm just curious if it may be a problem. The actual material doesn't seem to be deteriorating at all.
     
  6. yep, the surround can become unglued. If it's paper, glue it back if it's not torn.
     

  7. 95% of all cone speaker failures are mechanical. Ripped surrounds and such. Burnt voice coils are actaully pretty rare.

    I've seen plenty of drivers that weren't glued properly and the surround let go from the cone. This is a defect and is actually pretty easy to fix. Rips are much harder to deal with.