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Questions About Cleaning and Wiring JBL D140F's

Discussion in 'Amps and Cabs [BG]' started by count-me-out, Jun 29, 2016.


  1. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Hey y'all,

    This is my first post here, so I apologize if this isn't the best place to post about this or if I'm not quite used to the posting etiquette yet, but I sure could use some help!

    So I recently ordered some JBL D140F's on eBay from a seller with all 5 star feedback, and they arrived this week but are very, very dirty (not just dusty). I'm trying to load up my 200s cab before the end of next week as I'll be out of town for a bit after that and want to get everything tested in a timely manner.

    The first speaker has a lot of the packing material stuck to the cone (see pics), mostly on the dope, but its on both sides of the cone (some is under the edges of the basket). I tried blowing and using one of those squeezers for dusting camera lenses, but that didn't work. I tried very gently brushing it away with my hand, then a microfiber cloth, and that didn't work either. If I add a bit more pressure (about as much as I feel comfortable applying to a speaker cone - as much or less than I would for a flex test), I can get some of the material to either come off or loosen up so I can blow it off.

    The second speaker arrived today and it has a different issue. There seems to be a feather (?!?!?!) stuck to the cone, as well as a couple pieces that look like tiny wood chips, and then some little shiny bits that I can't identify.

    Also, I've never had speakers that used push-down terminals like these before, and one of them is bent a little (shown in pics as well)... Is that going to be an issue? And do you solder the wires to these terminals, or just insert them and leave them clamped down?

    Am I right to be so concerned about all of this? I'll be running a vintage tube head into this cab and the last thing I want is to wind up with a torn cone and blown speakers, and then have to possibly order a custom wound ultralinear transformer. I'm just concerned that some of these little pieces might damage the cone while its moving back and forth over time. And if you're not supposed to solder those terminals... if one of them is bent... I just don't know.

    Any advice you guys might give is greatly appreciated! Thanks for taking the time to read! :)


    1 - NMeEN3K.
    Speaker #1
    2 - YIzi1Sw.
    Speaker #1
    1 - yT8v7B3.
    Speaker #1, close up of the dope
    3 - pTbkQPQ.
    Packing Material
    2 - 9AD21NG.
    Packing Material close up

    4 - UodrFCq.
    Speaker #2
    3 - EvxgYdh.
    Wasn't kidding about the feather...
    2 - 6hzqtzL.
    Dented terminal (black)
    1 - MIzes2T.
    Undented terminals for reference
     
  2. AstroSonic

    AstroSonic Supporting Member

    Dec 10, 2009
    rural New Mexico
    None of that stuff matters as long as the speakers function properly. Heavy speakers require that good sense be used when shipping. Hopefully, you didn't pay for 'mint' condition drivers. I once received a JBL driver from a well rated seller with the cone nearly totally destroyed. It had been put into a shipping box that was then filled with foam peanuts. The cone was shredded. Anyways, your drivers appear to be in functional condition. Hook each one up (open air) and play some music at moderate levels (cone movement should be no more than barely perceptible) - listen for rattling and buzzing, signs of voice coil misalignment. If they sound like music (albeit bass shy), go ahead and use them. They are great drivers.
     
  3. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Bummer. Pick the big pieces and feather off with tweezers, don't worry about the little stuff, it won't matter.

    I would not attempt to bend the terminal post straight, it's possible to break them and that's bad. Check to be sure that the post is not loose, there is a nut behind the post that an eyelet terminal attaches and if it's loose it can result in an intermittent signal/noise.

    When wiring, it's almost certain that you will need to wire tip to black and sleeve to red (backwards from today's speakers) because your speakers use the legacy standard, and you will want them to match with today's standard in case you end up using a cabinet with another modern one.

    Search on the battery polarity test, you want each driver to move outward with positive voltage on the top and negative voltage on the sleeve. ALWAYS double-check JBL's, some aftermarket recone kits are wound to the modern standard, some are not. All factory kits should still be to the legacy standard.
     
    funkytoe, old spice and SirMjac28 like this.
  4. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Thanks so much for your response! It's a big relief to hear this.

    The reason I wound up buying these was because I managed to get the pair for less than the average price of one alone :) so all good on that front. Sorry to hear about the shredded cone you wound up with before - but glad to hear the seller I bought from didn't do as bad as he could have.

    So you recommend hooking them up outside the cabinet and testing them before loading them in? I've never done that but I can definitely give that a shot and keep an eye on the cone and listen for buzzing and rattling. Thanks so much for your advice!
     
  5. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Outside the cabinets at LOW power only.
     
  6. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    I didn't even consider tweezers, but based on your credentials I will definitely take that advice. Dang, thanks! I would've thought that would be too risky - I'll just be careful with 'em.

    Thanks for the tip on the polarity test. I'll give it a shot. These have been reconed - the seller said it was up to original spec, but this ought to tell me, haha! And I'll make sure to check if the nut is sturdy... if not, I may have some more questions for you :whistle::whistle::whistle:

    And just to clarify - I should use an eyelet terminal to connect the speaker wire to the post? Sorry, I'm very new to speakers without solder tabs.
     
  7. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Duly noted!

    :thumbsup:
     
  8. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Yikes... Well this is concerning. I just pulled them back out to look them over again and noticed this not-so-subtle hole in the cone on Speaker #1. Looking back at one of the pictures I took earlier, I can see it there. Can't believe I missed this.

    1 - oWjICL6.


    So, I don't know a whole lot about speakers, but I'm pretty sure this means I need to return at least this one. Please do correct me if I'm wrong folks, and I hope I am :dead:
     
  9. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    The eyelet terminal is what the tinsel lead wire from the cone solders to from the back side of the basket, not a user connection.

    The hole is not a big deal, this is a good place to use rubber cement to fill the hole plus 1/8" beyond hole. Maybe the guy will compensate you a little for the additional work?

    When shipping speakers like this, it's critical to protect the fronts from the packaging material (I use heavy cardboard. and to place the entire speaker in a plastic bag to keep the crap out.
     
    climber and SirMjac28 like this.
  10. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    You're a goldmine of help, agedhorse! For some reason working on speakers terrifies me :rollno:
    But it's definitely starting to seem less daunting!

    I've got a few tabs open looking at cone patching options... seems like there's a few ways to do this. Rubber cement the best way to go about it on a budget? Got any links to tutorials you'd recommend? I'm sure I can find some stuff, but I just wanna make sure whatever I do, I do it the right way. This is a good opportunity to get some experience here, thanks!
     
  11. AstroSonic

    AstroSonic Supporting Member

    Dec 10, 2009
    rural New Mexico
    Unfortunate, but not a necessarily a deal breaker. First see if the driver works. Do the low power music test - make sure that cone excursion is no more than barely visible (as mentioned in my 1st post). If it passes, then you must decide if you are willing to repair this very small hole. Really, it's not that big a deal, as long as you basically just want functional drivers. To repair that hole (about 3/16" diameter), first clean the area around the hole on the back side - use a water moistened (but not soaked) Q-tip. Then cut a 1 inch square piece of cotton/poly blend cloth. Color it with black magic marker. Work some aquarium glue into it (until it appears soaked), then place the cloth across the hole on the back side (for cosmetic reasons); work the cloth into the surround 'valleys' using a Q-tip. It will last for years.

    Also note that you need only wire the drivers so that they are in-phase (cones move forward and backward in unison). You can check for this during the music test; wire the two drivers in parallel. Place them against a wall (makes the bass easier to hear) so that they are tilted up, toward you. Listen to the bass. With no enclosure, the bass will be weak, but not totally absent. Rewire, switching one of the drivers wires. Listen again. The wiring with the strongest bass has the drivers working in phase. Using a magic marker, mark a terminal on each driver that are on the same wire when the drivers are in phase. Done.

    Short of good luck, the only way to avoid this kind of thing is to purchase from a knowledgeable seller, and pay for a near-mint pair. Still, you very likely have a functional set of drivers.
     
    Last edited: Jun 29, 2016
    SirMjac28 likes this.
  12. SirMjac28

    SirMjac28 Patiently Waiting For The Next British Invasion Gold Supporting Member

    Aug 25, 2010
    The Great Midwest
    Welcome to Talk Bass and yes the Horse Man is a walking Wiki for anything that uses electricity good luck with your new speakers.
     
    Doug Parent likes this.
  13. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    For this specific repair, rubber cement is the best way for the average person. I have some specialized filler adhesives that are different and better, but not the kind of thing you can easily buy in small quantities. The most important thing is that the adhesive is not brittle.
     
  14. jim nolte

    jim nolte

    Oct 26, 2006
    california
    A 200s(Sunn) with D140s' was my main cabinet for years mid '70s-'80s powered by a Ampeg V4B. Never felt wanting!
     
  15. Welcome Windy City dweller. You've got some very good advice to follow and it was wise to ask first.

    On the terminal post, if it goes up and down and grabs the wire good, you should be good to go.

    For future reference, rather than air pressure on a speaker, I would recommend a vacuum attachment with a brush, very gently. Or better yet, what I do is use a vacuum hose about 2" away and go at it with a soft brush. An acid brush or a disposable soft bristle paint brush (aka chip brush).

    I can't believe they didn't just drop them in a bag before packing. Especially with Instapack. Maybe send the pics to the seller and ask for a 15% refund to make it right.
     
  16. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Hey y'all, everyone here has been a huge help so far, and I can't respond to everything individually right now, but I do have another question - I'm trying to get ready for a quiet music test; the wiring harness in my cab uses connectors like this:

    2 - exu7idB.
    3 - ig63WZE.

    (picture shows them connected to the Pyle Drivers currently loaded in the cab)

    But they don't quite fit into the terminals on the new JBL's.

    Can I just drop some stranded speaker wire in there? Can't remember if it's 16 or 14 ga but... this stuff. 1 - siN4YY0.

    If that won't work, I can definitely swing by the hardware store tomorrow and look for some smaller connectors. If you guys can tell me what to look for I will make you rich as a Lannister (not really a cash offer, but man, I'd really appreciate it)!

    Thanks for ALL of your help thus far!
     

    Attached Files:

  17. Yes, those take bare copper fine. Probably best really.
     
  18. AstroSonic

    AstroSonic Supporting Member

    Dec 10, 2009
    rural New Mexico
    Just stick an inch of wire into one side of each connector (each has 2 rolled edges) and crimp gently with needle nose pliers. The insert into the JBL connectors.
     
  19. count-me-out

    count-me-out

    Jun 29, 2016
    Chicago
    Kinda like this? (found some thinner stranded speaker wire lying around that will actually fit in there)

    1 - 0O3cL7Z.

    So like, I'm basically running an inch of wire from the heat shrink'd connector that stems from my wiring harness, as a jumper into the JBL terminals? Sorry, aside from wiring speakers with solder tabs I've just only done PTP and eyelet board stuff, I don't know why I'm having such a hard time grasping the concept haha.

    For real Astro, you're saving me a big headache right now, I truly appreciate it.
     
  20. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Just cut the connectors off strip the wire and insert in the terminals.
     
    TinIndian likes this.