+ Reply to Thread
Results 1 to 11 of 11

Thread: 136A re-foaming

  1. #1
    Member dllyons's Avatar
    Join Date
    Feb 2004
    Location
    Zanesville, Ohio
    Posts
    96

    136A re-foaming

    Hello !
    I needed to replace the surrounds on my L300's a while back and I thought I'd try to do it myself, as I've refoamed smaller drivers and was successful in the past.
    I got one of them done and everything seems fine, but the other one, when playing heavy bass at higher volume levels, will drag the voicecoil. yipes !

    So I'm throwing the towel in and admitting I don't have the skills to do larger diameter woofer repairs. So, who in the heck is a good source to do that in the Ohio, or midwest region ? Any suggestions?
    My L300's have sat dormant for months and months and I need to let them live again.
    Suggestions anyone ?

    Thanks mucho !
    Dave Lyons - Zanesville, Oh = L300, L36, L40,
    L100a & L100a Century, J2050, S36AWII

  2. #2
    Senior Member edgewound's Avatar
    Join Date
    Jun 2005
    Location
    Southern California
    Posts
    2,574

    Re-suspend

    Quote Originally Posted by dllyons View Post
    Hello !
    I needed to replace the surrounds on my L300's a while back and I thought I'd try to do it myself, as I've refoamed smaller drivers and was successful in the past.
    I got one of them done and everything seems fine, but the other one, when playing heavy bass at higher volume levels, will drag the voicecoil. yipes !

    So I'm throwing the towel in and admitting I don't have the skills to do larger diameter woofer repairs. So, who in the heck is a good source to do that in the Ohio, or midwest region ? Any suggestions?
    My L300's have sat dormant for months and months and I need to let them live again.
    Suggestions anyone ?

    Thanks mucho !
    Sometimes a refoam is not enough to bring them back to life. It could very well be that the spider is too fatigued to be successful with just a refoam. A rubbing voice coil can be an indicator that the spider is done.

    If that's the case, short of a full recone, it's possible to replace both the surround and the spider. It's a pretty tedious job but it works well when done right.
    Edgewound...JBL Pro Authorized...since 1988
    Upland Loudspeaker Service, Upland, CA

  3. #3
    Member dllyons's Avatar
    Join Date
    Feb 2004
    Location
    Zanesville, Ohio
    Posts
    96
    Quote Originally Posted by edgewound View Post
    Sometimes a refoam is not enough to bring them back to life. It could very well be that the spider is too fatigued to be successful with just a refoam. A rubbing voice coil can be an indicator that the spider is done.

    If that's the case, short of a full recone, it's possible to replace both the surround and the spider. It's a pretty tedious job but it works well when done right.
    Thanks ! that's a consideration, but I'm more inclined to believe it was my ineptness to center the coils correctly on these bigger woofers.
    Edgewound- Do you work for a speaker repair place ? If so, should I ship them to you ? Or, who would you send them to for refoaming ? It doesn't have to be, but I'd prefer the midwest area.

    I've found places like 'Simply Speakers' and 'Speaker Repair Center' but I want good reputable repair. Maybe one of these companies can do it, but I'm not sure.

    I love my smaller JBL's that I've been listening to as an alternative, but I can't wait to get these L300's back in action.
    Dave Lyons - Zanesville, Oh = L300, L36, L40,
    L100a & L100a Century, J2050, S36AWII

  4. #4
    Senior Member edgewound's Avatar
    Join Date
    Jun 2005
    Location
    Southern California
    Posts
    2,574
    Quote Originally Posted by dllyons View Post
    Thanks ! that's a consideration, but I'm more inclined to believe it was my ineptness to center the coils correctly on these bigger woofers.
    Edgewound- Do you work for a speaker repair place ? If so, should I ship them to you ? Or, who would you send them to for refoaming ? It doesn't have to be, but I'd prefer the midwest area.

    I've found places like 'Simply Speakers' and 'Speaker Repair Center' but I want good reputable repair. Maybe one of these companies can do it, but I'm not sure.

    I love my smaller JBL's that I've been listening to as an alternative, but I can't wait to get these L300's back in action.
    Yes...I'm JBL Authorized Service...Since 1988

    I do all the work...and have done work for many members here. Thanks for asking.

    www.UplandLoudspeaker.com
    Edgewound...JBL Pro Authorized...since 1988
    Upland Loudspeaker Service, Upland, CA

  5. #5
    Senior Member
    Join Date
    Oct 2003
    Location
    Texas
    Posts
    1,097
    edgewound can correct me if I'm wrong, I know nothing of the 136A, but some guys advocate removing the dustcap and making sure there isn't any disintegrated foam from the vent stuck in the gap. I don't know if the 136A has a foam filter or a vent, but it'll make the coil hang up if it gets in there and melts.

    The reason I don't know any of this is because I just send my stuff to edgewound when it needs work.

  6. #6
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    8,475
    My 2 cents...

    Since the 136A is part of the classic sound of these vintage speakers, if they were mine, I'd send them to Edgewound and see what he could do to salvage the woofer. A typical repair center might "repair" them in any number of less than ideal ways... even a quality factory authorized center would follow JBL's guidelines and do a full recone with a 2235H kit. Not bad, but not original sounding either.


    Widget

  7. #7
    Senior Member 57BELAIRE's Avatar
    Join Date
    Feb 2005
    Location
    SoFlo
    Posts
    499

    "Frankenwoofers"

    Quote Originally Posted by Mr. Widget View Post
    My 2 cents...

    Since the 136A is part of the classic sound of these vintage speakers, if they were mine, I'd send them to Edgewound and see what he could do to salvage the woofer. A typical repair center might "repair" them in any number of less than ideal ways... even a quality factory authorized center would follow JBL's guidelines and do a full recone with a 2235H kit. Not bad, but not original sounding either.


    Widget
    I know I'm going to be assailed by some "purists" who regularly post on these pages, but
    I feel replacing the foam surrounds on certain models (136A) is futile at best.
    As the original owner, I replaced the foam on my L300 woofers twice in 20 years before
    finally switching to pleated cloth (ala PR15) and to my ears...they sound great, not to mention
    never having to deal with crumbling foam again.
    Since my listening room is nowhere near the ideal anechoic environment, I don't rely on charts,
    graphs and measuremnts to define my listening experience...just my ears.

    This observation is purly subjective as is the enjoyment of music in general so if "factory specs"
    are more important then by all means....have at it.
    OPUS POCUS

  8. #8
    Senior Member
    Join Date
    Apr 2003
    Location
    Toronto
    Posts
    3,745
    > Pleated cloth surrounds can handily allow an Fs down to around 25hz .

    > There are a few current woofers that take this approach ( including the new JBL 1501Fe I think it is ) .
    > The Altec/GPA 416-8C is another ( as well as the TAD 1601 line of woofers ).
    > Emulating some superficial aspects of their success is not necessarily a bad thing ( when done with restraint ) .

    Quote Originally Posted by 57BELAIRE
    I know I'm going to be assailed by some "purists" who regularly post on these pages,,,,,,SNIP
    ...they sound great,,,, SNIP
    Since my listening room is nowhere near the ideal anechoic environment, I don't rely on charts,
    graphs and measuremnts to define my listening experience...just my ears.,,,,

    This observation is purly subjective as is the enjoyment of music in general so if "factory specs"
    are more important then by all means....have at it.
    > Sometimes people get lucky in their adhoc modifications ( like I think you did here / though yours was more of an educated guess I believe, based on long-term observation ). A lot of times these mods won't work out .

    > ( Not that you want to know, but ; ) raising the Fs ( slightly ) by changing the mechanical Q will also proportionally increase the Qts of the woofer ( but still keep it within a very usable range ) allowing for a slightly "fuller" sound ( though this is most often over-whelmed by room acoustics, so as not to be that noticeable ) .

    > Any idea what the ( manufacturing ) source ( of your pleated surrounds ) were ?
    > As an experiment, I'm thinking of adding a more compliant surround ( foam or pleated ) to a 2225 to see what results .


  9. #9
    Junior Member Robbie4477's Avatar
    Join Date
    May 2010
    Location
    Denmark
    Posts
    10

    What to do 136A

    Hello I have a set of 136A from my L-300s as I can see they been re-coned with a 2235hkit I heard a few different stories that its not the best solution to add that kit with a expander ring ? would it be legitimate to install a set of 2235H drivers in a set of L-300s ? and would it lower there value ?from a collectors point ?and what the best solution do with a 136A basket

  10. #10
    RE: Member when? subwoof's Avatar
    Join Date
    Aug 2003
    Location
    fingerlakes region, NY
    Posts
    1,850

    2225 foam

    I have a dozen ex condition 2225's from an install and plan on changing the surround to either foam or a durable rubber ( like the automotive stuff ) and adding some weight to the cone similar to aquaplas. new tinsels, inside foam, etc.

    not sure where the specs will be when compared to the 2235 or 2234 but well within the ballpark to get all of these "rescued" 433X cabinets working again at an affordable price.

    sub
    << too many to list anymore >>

  11. #11
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    8,475
    Quote Originally Posted by Robbie4477 View Post
    Hello I have a set of 136A from my L-300s as I can see they been re-coned with a 2235hkit I heard a few different stories that its not the best solution to add that kit with a expander ring ? would it be legitimate to install a set of 2235H drivers in a set of L-300s ? and would it lower there value ?from a collectors point ?and what the best solution do with a 136A basket
    The 2235H kit is the best solution. Your alnico magnets may need recharging, but other than that, a properly installed 2235H kit in a 136A frame is the factory recommended solution.


    Widget

+ Reply to Thread

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Speaker Re-foaming
    By Allanvh5150 in forum Lansing Product DIY Forum
    Replies: 5
    Last Post: 06-25-2007, 02:42 PM
  2. Re-foaming Le14's
    By L100t Owner in forum Lansing Product Technical Help
    Replies: 3
    Last Post: 03-18-2006, 11:07 AM
  3. Question: Re: Re-foaming drivers
    By LE15-Thumper in forum Lansing Product Technical Help
    Replies: 24
    Last Post: 04-27-2005, 08:45 PM
  4. Foaming a 2012H....??
    By subwoof in forum Lansing Product Technical Help
    Replies: 0
    Last Post: 05-19-2004, 07:00 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