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My JBL4312 RestoMod Project

Discussion in 'The Lansing Legacy' started by ictwoody, Jan 14, 2018.

  1. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    This new forum seems like the perfect reason to post a thread about my little project. I was gifted a pair of 4312’s that were in decent shape... but far from perfect. When I got them one of the port tubes had come loose and fallen into the speaker. So after letting them sit in a closet for months, I finally decided to get into them.

    Originally I was just going to open up the one speaker, fix the port tube and put it back togeather and flip them. But then the designer in me took over and I was like... what’s another project on top of the other half dozen or so I already have!

    I quickly decided I wasn’t going for a restoration. JBL purists might gasp... but I like to make stuff the way I find it cool and I find its pretty easy to find people who like my style when it’s time to sell. Plus... these weren’t museum pieces and non-sequential serial numbers etc...

    I decided I want to go with JBL blue baffles. Because everyone loves that! I sanded the cabs and applied two coats of Osmo PolyX Oil. Fresh coat of black on the backs. You can see the plugs where I fixed the holes from where these were flown/hung in a studio in a past life.

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  2. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    Both the mids and the tweeter domes were bashed in. I decided to go with repop tweeters from Midwest Speaker Supply and then using their replacement domes I redomed the mids. I thought about trying to fix the tweets, but the anodizing was faded and there was some cone discoloration etc... and I’m lazy.

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    Last edited: Jan 14, 2018
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  3. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
    2,707
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    Last night I tackled the crossovers. All new caps following the parts listed in a thread here on AK. New LPads as well cause why not. I decided to use some terminal strips I had on hand cause I might swap the stock wire in the future for Duelund DCA wire. We’ll see.

    I used the parts listed for an “Improved Original Sound.”

    The last pic shows the stock crossover vs my own.

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  4. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    This week I’m getting new badges/foilcals made from my own design (I’m a graphic designer) which are an homage to the originals, but suitably custom for me. I think the aluminum will look great with the blue and then I’ll recover the grills with new black cloth for when you don’t want to be obnoxious.

    Here’s my working mock-up.

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  5. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    I’ll post more as I keep moving forward on them. Hope to have them wrapped up by next weekend.

    - Woody
     
  6. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    Made a little progress tonight. Got the crossovers re-installed. Also had some decent 5-way binding posts in my stash that fit the existing holes PERFECTLY!! No more stupid spring clips!

    The badges are to the engraver for a test cut of the pattern. If they fit okay then I’ll place the order. All that’s left is to install the drivers and badges and put the new grill cloth on the grills.

    Should be able to wrap them up this weekend and then I can start on the stands.

    - Woody

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    Last edited: Jan 16, 2018
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  7. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    Drivers are installed. They look good. Mirror imaged pair. I even installed the drivers mirror imaged where the leads are visible on the cones of the woofs and mids.

    Just need to recover the grills and get my badges. Engraving shop is being slow.

    - Woody

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    Last edited: Jan 25, 2018
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  8. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    Got the grills recovered. Badges are final and at the engravers. I probably won't have them until next week. So close!!

    - Woody

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    Last edited: Jan 25, 2018
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  9. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    First listen. Almost done.

    - Woody

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    Last edited: Jan 28, 2018
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  10. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    Post #10 reserved.
     
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  11. twiiii

    twiiii Addicted Member

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    Over the years I have heard some outstanding JBL. Right now my first choice would be 4435's if I had more money DD67000. But at one time I had to choose between a Paragon, Klipsch Corner Horns and Concert Grands. Investment wise I made the wrong choice. The Paragon was the easy winner. I chose the most flexible of the three, with the best bass and smoothest high end.
     

     

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  12. Speedbump71

    Speedbump71 Buried in speakers Subscriber

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    Beautiful work so far. I am in the middle of a Forte II project, but my L200's are coming up next. Cant wait to see more pics.
     
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  13. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    Updated post #6.

    - Woody
     
  14. MCM_Fan

    MCM_Fan AK Subscriber

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    Those are really sharp looking. Have you thought about making a few extras and selling them? And/or making some for other JBL models?

    I can't stand the cheap plastic banners on my 4301Bs. They cheapen the appearance of an otherwise very fine, very attractive speaker:

    [​IMG]

    Which is why I won't be re-installing them when I recover my grills with some new cloth. I'm going to go with the classic JBL badges instead:

    [​IMG]
     
  15. MCM_Fan

    MCM_Fan AK Subscriber

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    Rather than quote every one of your posts, I'll just add a few general comments:

    The blue baffles look GREAT. What paint did you use? Do you have the mixing codes, or a link to the ones you used?

    The crossovers look very clean. Great job! I'm a bit obsessive when it comes to rebuilding crossovers. I shorten the leads as much as possible (you may have noticed that all the original components come with 6" long leads, even if 1" would have been plenty). I separate the inductors and orient them at 90-degree angles to minimize any coupling, use bypass caps for all tweeter circuits. etc.

    I agree on replacing the stock spring clips with real binding posts. I just installed a set of the Dayton Audio BPA-38SN Heavy Duty binding posts on my 4301Bs last night. I usually go with the gold finish, but went with the satin nickle this time. Not that many people will ever see them, but I think they look really sharp.

    [​IMG]

    I look forward to following the rest of your thread through to completion. What grill cloth are you using, the standard dark blue? What is your source?
     
  16. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

    Messages:
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    Location:
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    @MCM_Fan I have used those binding posts before... they are really good. I'm not totally sure where I got the ones I used... but they worked perfectly for these. For the paint I used the paint code from another thread here on AK where a Ace Hardware employee posted up the mix. I just showed the paint kid the sticker on my phone and he punched it all in and mixed it. Looks good to me! Here it is below.

    As far as the badges, I'll have to see how they turn out and how much they cost. I doubt it would be very profitable to make it worth dealing with it. If they turn out well then I supposed I could provide the files to people and then they would just have to source a local vendor.

    As for grill cloth, I just added a yard of black cloth from Parts Express to my crossover parts order. I decided to go with black so that if the blue was ever too intense you could pop on the grills and have a reprieve. Maybe I'll buy a 2nd set of new repop grills off eBay to just have a blue set too. :)

    One thing I'm trying to decide right now is do I use any gasket or rope caulk when I re-install the drivers? They didn't have any from the factory.

    - Woody

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  17. Porkloin

    Porkloin Oscar Heil Groupie

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    Fantastic, well detailed project. The badge is a great improvement. Have you figured how the concept is going to become a reality yet?
     
  18. ictwoody

    ictwoody I like vintage gear — my preamp is from 2007. Subscriber

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    I am a graphic designer for a living. I sent the art over to a engraving/trophy shop I’ve worked with for years. I’m just waiting for him to test cut me some scrap with their laser to confirm my fit before they do the actual badges on the brushed aluminum. Hopefully they get the test cut done this week.

    I will update as soon as I have them.

    - Woody
     
  19. lokerola

    lokerola AK Subscriber Subscriber

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    Great work - they are looking fantastic.
     
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  20. MCM_Fan

    MCM_Fan AK Subscriber

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    Thanks. I assume the base paint is this:

    [​IMG]

    They also offer an exterior flat enamel, but the product code for that one starts with 127.

    I just have some very tiny chipped areas, mostly around the woofers, that need touched up. I may be better off having them do a paint match for my specific speakers since there really is no one single shade of JBL Blue. It varied over time.
     

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