Page 2 of 2 FirstFirst 12
Results 16 to 25 of 25

Thread: JBL L100 midrange !!!

  1. #16
    Heather [Senorita member] hjames's Avatar
    Join Date
    Nov 2005
    Location
    NoVA - DC 'burbs
    Posts
    8,341
    Quote Originally Posted by jbl View Post
    What is the yellowing of the woofer on the left?
    Some time around smokers, perhaps?
    2ch: Oppo, JoLida 502CRC, JBL L212, 18ti,240ti; Heath AS101, Von Schweikert VR4
    7.1: Oppo BDP103D, B&K, UREI 809A, JBL B460

  2. #17
    jbl
    Guest
    Quote Originally Posted by hjames View Post
    Some time around smokers, perhaps?
    You may be right. No one smokes at home and my 1975 L100s don't show any discoloration. Thomas, any pealing of the Aquaplas?

  3. #18
    Senior Member
    Join Date
    May 2009
    Location
    California
    Posts
    1,619
    Quote Originally Posted by jbl View Post
    You may be right. No one smokes at home and my 1975 L100s don't show any discoloration. Thomas, any pealing of the Aquaplas?
    Every thing is blamed on smokers! (although I agree, tobacco smoke CAN indeed foul things up)
    I've seen the yellow glue joints on woofers with pristine white cones, so that's enough empirical evidence for me that something else is going on
    May even be the paricular batch of glue
    I've have good luck with white Aquaplas woofers and have only experienced small chips on the edges when removing hardened Lansalloy surrounds
    I don't think it's anything to worry about
    Thomas

  4. #19
    jbl
    Guest
    Makes sense.

  5. #20
    Senior Member
    Join Date
    May 2009
    Location
    California
    Posts
    1,619
    Speaking of L100 mids; how tightly sealed does the mid chamber need to be? My seal, as far as woofer pressure or turbulence goes (the mid's little chamber or cup) is fine and solid to the baffle and the wires are well sealed at the entry point in the little cup.
    These are an original owner pair and the drivers have only been in and out once, but I can feel that those crummy little wood screws wouldn't need much to strip out of the MDF baffle.
    I just snugged mine up (a couple not as "snug" as I would like) and counted my Blessings.
    Neither of my cabs used a gasket on the mids either.
    "OK" or should I try to tighten up those holes or go with some longer screws?
    Would they benefit from gaskets? (O-ring seals)

    Thomas

  6. #21
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    7,984
    All the drivers in my L100's had gaskets. "O" rings on the mid and woofer a flat paper gasket on the tweeter. There are groves in the frames for the woofer and mids where the "O" rings fit.

    Rob
    Attached Images Attached Images   
    "I could be arguing in my spare time"

  7. #22
    Senior Member
    Join Date
    May 2009
    Location
    California
    Posts
    1,619
    Quote Originally Posted by Robh3606 View Post
    All the drivers in my L100's had gaskets. "O" rings on the mid and woofer a flat paper gasket on the tweeter. There are groves in the frames for the woofer and mids where the "O" rings fit.

    Rob

    Hello!
    Yes, I can see the groove, but no O-ring.
    I do have the proper woofer O-rings and the paper gaskets on the LE25s.
    Just wondering if any response is lost on the mid with the missing (never installed) O-ring?
    They were never there on this pair.
    Don't know if the mid's enclosure has to be "sealed" as in acoustic suspension sealed or just sealed well enough to prevent the woofer from interfering?

    Thomas

  8. #23
    Senior Member rdgrimes's Avatar
    Join Date
    Aug 2008
    Location
    New Mexico, USA
    Posts
    2,172
    The mids mainly need to be sealed on the inside can. Sealing the outer flange isn't a huge deal, but it really should be well sealed. I'll wager there are o-rings around that will fit the driver.

  9. #24
    Senior Member
    Join Date
    May 2009
    Location
    California
    Posts
    1,619
    Quote Originally Posted by rdgrimes View Post
    The mids mainly need to be sealed on the inside can. Sealing the outer flange isn't a huge deal, but it really should be well sealed. I'll wager there are o-rings around that will fit the driver.
    Hello,
    Yes, I'm sure there are. Problem is sourcing them. I've long ago given up on trying to source little odds and ends like this from JBL. They don't seem very motivated to fool with this sort of stuff.
    I would think they would/should be the hollow type like on the woofers to allow for a nice compression seal without stressing the mounting flange, not to mention the lousy wood screw holes.
    I'm going to have to reinforce my screw holes too, during this R&R to double check wiring I became aware of the fact that they're starting to get to that point where they're going to stop getting snug soon and just spin 'round and round.
    Don't know why they didn't use T-nuts on these. This big grain density MDF stinks for wood screws

    Thomas

  10. #25
    Senior Member
    Join Date
    May 2009
    Location
    California
    Posts
    1,619
    Quote Originally Posted by Robh3606 View Post
    They could have been manufactured at different times. Take a look at the label and the color of the tweeter surrounds. The originals were yellow. Latter ones were black.

    Rob
    I know this thread is ancient; doing some research and came across it.

    I thought the original LE25 tweeters had the dark reddish orange surrounds and the later black.

    When were they ever yellow? LE20 or LE25s?

    Or if you're talking LE5-2s I've never seen a yellow surround on one of those either?

    Please advise

    Thank you

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. PA Midrange Help
    By 2$Bill in forum Lansing Product DIY Forum
    Replies: 20
    Last Post: 12-22-2012, 07:28 AM
  2. le5-12 midrange
    By brad6285 in forum Lansing Product General Information
    Replies: 7
    Last Post: 01-08-2012, 04:39 PM
  3. L-96 Midrange Out
    By Roundsound in forum Lansing Product Technical Help
    Replies: 4
    Last Post: 02-01-2009, 09:04 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •