Author Topic: JBL 4311b Control Monitors  (Read 100708 times)

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #15 on: April 08, 2019, 04:51:12 PM »
If you decide they aren

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #16 on: April 08, 2019, 04:52:06 PM »
Crap

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #17 on: April 08, 2019, 08:39:58 PM »
Here's some pics.














The cabs can be fixed, I'll need a tetanus shot update. I guess the next step is determining which drivers work. I don't think that mid can be saved, maybe I'm wrong? 

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #18 on: April 08, 2019, 11:35:23 PM »
Well, I looked at it and thought "that mid is no problem but I don't know if that cabinet can be saved", so we each must have different specialties.   Get rid of the mold from the drivers with a dry paintbrush then let them sit in the sun for a day.   The cabinets are cleaned easily enough, I just don't know how to repair the water split joint.   The bottom front edge of the one can just get a new piece of veneer glued in.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #19 on: April 08, 2019, 11:36:58 PM »
What I was going to say before and it cut me off is that if you decide to not restore them I would trade you a defective Dual for them as is and we can each play to our strengths.

I may even have two Duals for you to use that jig on.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #20 on: April 08, 2019, 11:38:15 PM »
Oh, and not tetanus, but wear a mask.   Mold can be dangerous.

Offline Comten

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Re: JBL 4311b Control Monitors
« Reply #21 on: April 09, 2019, 07:03:33 AM »
<snip>
The cabinets are cleaned easily enough, I just don't know how to repair the water split joint.   The bottom front edge of the one can just get a new piece of veneer glued in.

Please advise if you find a place in SW PA that can repair the cabinet split at the joint.

Thanks!

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #22 on: April 09, 2019, 08:12:48 AM »
<snip>
The cabinets are cleaned easily enough, I just don't know how to repair the water split joint.   The bottom front edge of the one can just get a new piece of veneer glued in.

Please advise if you find a place in SW PA that can repair the cabinet split at the joint.

Thanks!

Speaking only for myself, I would be exploring options of how to do it myself.   I wouldn't be looking to pay someone else to do it.

Online MacGeek

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Re: JBL 4311b Control Monitors
« Reply #23 on: April 09, 2019, 08:23:48 AM »
Considering the moisture to which these must have been exposed, I am concerned about the condition of the x-over and pots.  Also, any damping material inside the cabinets is suspect, as is the back of the drivers.

If these were mine, I would start by completely disassembling them to fully assess any damage.  The cabinet split might be repaired from the inside while they are apart.
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Offline Comten

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Re: JBL 4311b Control Monitors
« Reply #24 on: April 09, 2019, 09:13:29 AM »
Considering the moisture to which these must have been exposed, I am concerned about the condition of the x-over and pots.  Also, any damping material inside the cabinets is suspect, as is the back of the drivers.

If these were mine, I would start by completely disassembling them to fully assess any damage.  The cabinet split might be repaired from the inside while they are apart.

Time and tools... Have neither.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #25 on: April 09, 2019, 09:30:43 AM »
Considering the moisture to which these must have been exposed, I am concerned about the condition of the x-over and pots.  Also, any damping material inside the cabinets is suspect, as is the back of the drivers.

If these were mine, I would start by completely disassembling them to fully assess any damage.  The cabinet split might be repaired from the inside while they are apart.

Absolutely.

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #26 on: April 09, 2019, 08:03:32 PM »
I'm hoping to get these apart tonight/tomorrow. While wearing a mask. I got enough issues with the pollen explosion, don't need to double down with inhaling mold. MacGeek brings up a good point that the guts of these could be a horror, I'm hoping the mold is mostly on the outside.

I've got the tools here...time is the hard part. I'm no pro woodworker, but you don't get there without trying. At first glance, I planned to remove that wasted bottom and try to replicate as close as possible.

STaL, I appreciate the offer of the Duals. My wife would like me to try and restore these, if possible. It would be payback for a 40 yr old rifle I gave her dad to restore. I let him keep it when he was done, I'd be too tempted to do some backyard pest control. That said, if I get to the point of frustration with them, I'll let you know.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #27 on: April 09, 2019, 09:14:56 PM »
I'm hoping the mold is mostly on the outside.


Hissing cockroaches are more likely on the inside of a ported speaker.   I never bring a dodgy ported box into the house without tearing it apart first and making sure it's all clear.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #28 on: April 09, 2019, 09:16:35 PM »

STaL, I appreciate the offer of the Duals. My wife would like me to try and restore these, if possible. It would be payback for a 40 yr old rifle I gave her dad to restore. I let him keep it when he was done, I'd be too tempted to do some backyard pest control. That said, if I get to the point of frustration with them, I'll let you know.

I'm happy to provide an escape hatch should you need one.   I know it's very unlikely that I will ever get to the Duals.

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #29 on: July 22, 2019, 10:15:31 PM »
Couple of new pics.






Yeah, yeah the grain on the new bottom...or is it really the top  ??? isn't going the right direction. It's what I had lying around that was close to the correct thickness. Couple passes through the planer and it fit right in. Plus, I doubt it affects the sound.  >:D

More coming including a fairly ratty cone repair. The ripped mid may need replaced, the dustcap surrounds are aluminum and this one is real wavy. I think I got it glued back together, but we'll see.

The crossovers look good, minus some corrosion on the one that was wet. I'm going to hold off doing caps until I get them put back together and listen to them. The caps in there look pristine, but we'll see how they sound.