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Need info Jbl-l19

Discussion in 'The Lansing Legacy' started by Kwb, Aug 20, 2018.

  1. Kwb

    Kwb AK Subscriber Subscriber

    Messages:
    137
    Location:
    So Illinois
    I recently acquired a pair of L-19's in need of re-foaming. Starting researching "how to's" I noticed the center cone on images I looked at was inverted (concave). Mine are convex. They are jbl woofers with serial numbers.
    Any reason why my center cone would be different?
    Thank you in advance for any guidance.
    Keith
     

     

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  2. MCM_Fan

    MCM_Fan AK Subscriber

    Messages:
    2,467
    Location:
    Oregon
    Congrats, you have the original dust caps intact. That's the way they left the factory. Consider yourself lucky someone hasn't butchered them by replacing the original dust caps with ill fitting, incorrect generic replacements.

    The L19s are GREAT speakers. I restored a pair and gave them to a gal I was dating.

    Get the foams from Rick Cobb and install them correctly (foam glued to the rear of the cones). Use Rick's CD for centering the cones. No need to destroy those original dustcaps. I did two pair of the 116H (L19As and 4301Bs) woofers using Rick's foams and they turned out perfect - dust caps intact, looking, and sounding, like the day they left the factory.
     
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  3. Zonker92

    Zonker92 All shiny and chrome Subscriber

    Messages:
    7,167
    Location:
    Central CA
    Actually, the 116A or 116H dust cap should be concave; see:

    [​IMG]
     
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  4. MCM_Fan

    MCM_Fan AK Subscriber

    Messages:
    2,467
    Location:
    Oregon
    Oops, I misread the original post. I though he was saying his are concave. Concave is indeed "correct" and original. As are my L19As"

    [​IMG]

    And my 4301Bs:

    [​IMG]
     
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  5. MCM_Fan

    MCM_Fan AK Subscriber

    Messages:
    2,467
    Location:
    Oregon
    So, to re-answer your question...

    Someone who didn't care about authenticity refoamed them, sliced off the beautiful original concave dust caps and slapped on cheap, generic replacement dust caps. With such little attention to detail, I'd also recommend you check to see if the new foams are glued to the front, or back (correct way) of the cones.
     
  6. Kwb

    Kwb AK Subscriber Subscriber

    Messages:
    137
    Location:
    So Illinois
    Thank you all very much for the replies and your knowledge.
    I must say though, I'm still confused which way the dust cap should look. I'll post a pic of mine in current condition.
    Also, where might I purchase the Rick Cobb products?
    Thanks,
    Keith 20180822_210017.jpg
     

     

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  7. turnitdown

    turnitdown Well-worn member Subscriber

    Messages:
    1,859
    Location:
    Tallahassee, FL
    concave goes in - like a cave. Your dust caps are on backwards. I don't know of anyone testing to see if there is a sonic difference.
     
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  8. Marine0811

    Marine0811 I love it loud! Subscriber

    At least whomever replaced the foam put it on the back of the cone
     
  9. ivandezande

    ivandezande Super Member

    Messages:
    1,703
    Location:
    Twin Cities
    rcobb@tampabay.rr.com may still be his email. Google is your friend here.
    Nice speakers, be sure to recap as well as refoam.
     
  10. mech986

    mech986 Text ↓ optional Posts:>18,000 Subscriber

    Messages:
    19,286
    Location:
    La Habra, California, USA
    KWB, if both dustcaps were replaced as convex, they probably used a shimming method of voice coil centering during the refoam. If both woofers are done this way, the dust cap probably is wider than the original to hide the old glue line and would not be easy to restore to concave cleanly, cosmetics wise. I’d Leave them as they are and reform using the test sine wave centering method, then use them. If you want the absolute original look, the 116A or H woofers come up frequently on eBay and you could always sell yours to compensate.
     
  11. Kwb

    Kwb AK Subscriber Subscriber

    Messages:
    137
    Location:
    So Illinois
    Thanks Mech for the info.
     

     

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