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Can speakers fail from age?

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  • Can speakers fail from age?

    I'm building a prototype box for a friend of mine using brand new old stock JBL G135 woofer with a Radian HF driver with bi-radial horn.

    He has a lot of old JBL inventory he purchased years ago that been sitting in his warehouse. The G135 was in an unopened box and even though it looks perfect it is distorting really badly. It sounds like its blown. The test signal was checked on a different speaker and was fine to rule that out.

    Currently the box is being biamped until an appropriate crosserover can be obtained. My question is will age deteriorate a speaker that has been sitting in a shelf for a couple of decades?

    I have three more unopened G135s that I will swap out and test.

    Don


  • #2

    Did you try rotating it? If the voicecoil is rubbing that sometimes "fixes" it.


    "We Have Met the Enemy and He is Us" - Walt Kelly​

    Comment


    • Don Davis
      Don Davis commented
      Editing a comment

      We had it out in order to add some dampening material and I doubt it went back in that same rotation. It didn't make any difference.


  • #3

    I have seen very old speakers that failed from age, but it is obvious when looking at the speakers. I had one set of JBLs where the surrounds deteriorated so badly the cone was no longer even attached to the frame. Yes, age CAN make them fail, but these were close to 25 years old, and it was easy to see what and why they failed. This is NOT like what you describe.

    Comment


    • Don Davis
      Don Davis commented
      Editing a comment

      He's a JBL dealer/sound co. and he told me he bought them from JBL's discontinued program way back when.

      The surrounds look like new. Now I'm anxious to test the others.


  • #4

    Don Davis wrote:

    I'm building a prototype box for a friend of mine using brand new old stock JBL G135 woofer with a Radian HF driver with bi-radial horn.


    He has a lot of old JBL inventory he purchased years ago that been sitting in his warehouse. The G135 was in an unopened box and even though it looks perfect it is distorting really badly. It sounds like its blown. The test signal was checked on a different speaker and was fine to rule that out.


    Currently the box is being biamped until an appropriate crosserover can be obtained. My question is will age deteriorate a speaker that has been sitting in a shelf for a couple of decades?


    I have three more unopened G135s that I will swap out and test.


    Don




    If you push evenly on the cone, can you feel or hear any rubbing or scraping? It's extrememly rare but certainly possible that the speaker was defective from the factory...or from whatever source sealed the box. Also if the box was dropped the speaker could be damaged from that. I never trust packaging as a means of determining whether an old item is "original" or "factory", as there are ways of faking packaging.

    Write something...

    Comment


    • Telecruiser
      Telecruiser commented
      Editing a comment

      I have a set of JBL L-100's that I bought new in 1976. They get used at my shop daily and still sound great.


  • #5

    Ok here is my two cents.  If the suspension /web is good then the cone is not going to sag enough to rub on the pole piece/magnet structure.  If a loudspeaker gets to the point where it is rubbing because of sagging then it is time for a recone eh?

    BTW in my experience the rotation thing of the loudspeaker is BS...

    The web and suspension should hold the voice coil/former centered in the gap.

    If the suspension and web are worn out then of course you will have sag and rub

    I rest my case!  Aged get my back on this!

    Comment


    • Guitarman63
      Guitarman63 commented
      Editing a comment

      So, I am curious if the speaker rotaion worked. I recently purchased 2 jbl SR 4715A cabs (2x15 sub) it is loaded with 2226H speakers. These speakers were from a night club and you could scrape off the nicotene with a knife lol.Long story short hooked up Crown Macro 3600 and one of the speakers started distorting and raising hell but not constantly. pulled speaker and pushed on cone, no scratching sound. Thought I saw light coming from ports at one time when it was distorting? Do V.C. ever get weak? could it be dust or something inside? there are 3 air ducts on the magnet for cooling that have fine mesh screen so I doubt any dust got in but you never know. I have my speaker guy on deck for re-cone, But I think I will try rotation first. Won't cost anything but time!


  • #6
    The 2226 does not generally suffers from anything except prior misuse and abuse. A proper recone is in order, this is why I always recommend extreme care when buying used speakers.

    Comment


    • Guitarman63
      Guitarman63 commented
      Editing a comment

      I just tried the speaker "rotation" and it did not work. What I did find though is the surround is split on the other speaker I thought was fine. I have decided to go ahead and have all four reconed ($ OUCH!) luckily though my speaker guy is a really good friend and gonna do the work cheap. So my great deal on 2, 2x15 JBL sr subs is'nt gonna be a "great" deal after all. It sucks, but sunny side is I will have great sounding bottom end. Agedhorse is right "I always recommend extreme care when buying used speakers." 

       


  • #7

    I had time to do some testing this weekend. The first woofer tested was indeed bad. I swapped it out with another and fixed some problems with the box and now things are looking pretty good.

    I'm wondering if these woofers where really NOS or my friend just forgot they were used years ago.

    Thanks for all the replies.

    Comment


    • drumstix
      drumstix commented
      Editing a comment
      Building some new monitors Don?


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