Author Topic: JBL 4311b Control Monitors  (Read 99142 times)

Offline MacGeek

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Re: JBL 4311b Control Monitors
« Reply #30 on: July 23, 2019, 08:31:06 AM »
Nice work so far.  I don't have some of the tools, like a planar, but if I did I might not have the ambition.
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Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #31 on: July 23, 2019, 10:04:16 AM »
Yep.   That was a lot more work than the pictures may lead one to believe.

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #32 on: July 23, 2019, 01:28:47 PM »
Definitely not fun raising sawdust on hot, humid days.

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #33 on: July 25, 2019, 08:52:59 PM »
Put them all back together today, except one woofer screw. JBL used T nuts for the woofers. If you over torque or put too much pressure on them removing them you get a nice little mess. I tore the t nut right out of the particle board. Used sawdust and glue in multiple layers to fix the missing chunk. Anyhow, all back together to check the L pads and drivers. Everything works. I

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #34 on: July 25, 2019, 08:54:27 PM »
Ack, got cut off. Pics later.

Any cap recommendations? Need 3.0 and 8.0.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #35 on: July 25, 2019, 10:25:52 PM »
I've done that before.   I cut a piece of 3/4" plywood and glued it into the space.   I figured it was something to grab into and extra bracing.   I just had to find a 1" longer bolt.

Offline scorpio333

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Re: JBL 4311b Control Monitors
« Reply #36 on: July 30, 2019, 05:03:33 PM »
I had other photos, not sure where they went. Anyhow, here's a few of the Lpads and one of my "fixed" mids. All four L pads work great, pretty surprised. New caps should arrive tomorrow.













After the caps go in I need to make a set of grilles. While I didn't ruin the foilcals removing them, they were pretty ratty. I may not put them back on and instead make grilles that cover the whole front of the cabinet with some holes for the knobs. The cabs are ok enough, but there are some other swells and veneer damage. That said, I think I'll call it a day and enjoy the sounds they make. While the JBL purists may go bonkers over that decision, effort vs result is hitting diminishing returns and new cabinets won't make them sound better.

Offline Sir Thrift-a-Lot

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Re: JBL 4311b Control Monitors
« Reply #37 on: July 30, 2019, 10:16:43 PM »
IIRC, there is somewhere on the internet that you can buy repro foilcals.

The folks at Lansing Heritage would know for sure.