JBL L200 Studio Masters-Pics

For sure! IRCC, my arms would just reach far enough around to grasp the front edges from behind....And...LIFT!
But getting them thru doorways that way, with arms out, turned out to be an 'issue'.
Might partially explain the burst disc years later....
I once hired UW varsity wrestlers to help me move, and they DID hoist them one at a time, each.
Maybe try a bit of cammo paint to 'sneak' them in place w/o anyone noticing?
Or go back thru the British 'funnies' from WWII for ideas?
Good luck!
:beerchug:
No way they will be upstairs anywhere! My wife is the major obstical, all 120lbs of her!
 
So I've been really enjoying these. Big effortless un-distorted sound at any volume. Recently I was hearing some cabinet vibrations from one cab.
So I pulled the woofer and while inspecting the interior, pushing & pulling for any signs of something loose, I discovered the cross brace the tweeter bracket screws to was loose from the cabinet. The original glue had let go. Just a tiny bit of movement.
So I went in and epoxied it along the bottom where it was glued to the back panel of the cab.
So cool to be the first to open this up since it was built. Here's a look inside. I'll report back once it's back together.
Glenn
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Someday when you are in there poking around, crack open one of those compression drivers and see what the foam looks like on the back cap. After all these years likely it will be just starting to disintegrate or worse' has completely broken down.. I think there are factory replacements around, I made my own.. good till the next owner gets em after I have said my goodbyes at the pearly gate..
 
Someday when you are in there poking around, crack open one of those compression drivers and see what the foam looks like on the back cap. After all these years likely it will be just starting to disintegrate or worse' has completely broken down.. I think there are factory replacements around, I made my own.. good till the next owner gets em after I have said my goodbyes at the pearly gate..
Yeah, I've been thinking about that. Once the foam hits the crapper, how is the sound effected?
 
Yeah, I've been thinking about that. Once the foam hits the crapper, how is the sound effected?
Well that's a question I probably couldn't answer but when that foam does go it gets very sticky and will stick on that diaphragm for one. Possible ringing off the back cap from nothing left to deaden it could also be heard I suspect. I didn't notice that much sq improvement after doing mine, but those had just started their decline and only a little bit had crumbled and stuck on to the diaphragms.
 
Well that's a question I probably couldn't answer but when that foam does go it gets very sticky and will stick on that diaphragm for one. Possible ringing off the back cap from nothing left to deaden it could also be heard I suspect. I didn't notice that much sq improvement after doing mine, but those had just started their decline and only a little bit had crumbled and stuck on to the diaphragms.
Yeah, I should bite the bullet and just do it.
 
I’ve done that several times. Ok, I’ll keep going.
Yeah all kidding aside it will be super easy to pop the 4 screws on the cap and take a quick look for crumbling. If it is intact, just put the cap back on and forget about it,you probably have years. The foam will likely be in pretty fragile shape so don't push on it with your fingers if you intend to keep it in there. . If you do take it out you will want to pull the leads to the diaphragm at which point you should get yourself a bronze #2 Phillips and be very careful to hang onto those steel screws! That magnet is very powerful and those diaphragms delicate.l
 
Actually, after looking at the pictures I taken when I pulled my LE85's apart it looks like it could possibly have been safer for me to pull the other end of the jumpers that go to the binding posts instead of how I did it in order to replace the foam. But even so you still should take that diaphragm off (3 screws) while it's opened up as it will be just too vulnerable sitting on that huge magnet to any small bits of metal getting close. Cannot stress enough to keep the work area completely clear of any ferrous bits... Take care in there!
 

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If the foams look good, and you want to keep them, don't even touch them. At this age, they will literally disintegrate at your touch. Mine were doing this over 10 years ago, so...

When I replaced mine, I used the carpet padding that looks like different colored "head cheese." I just cut a circle, cleaned out the old foam, and used some spray adhesive on the padding to attach it.

Is this the best choice of materials??? :dunno: But seems to do it's job.
 
Actually, after looking at the pictures I taken when I pulled my LE85's apart it looks like it could possibly have been safer for me to pull the other end of the jumpers that go to the binding posts instead of how I did it in order to replace the foam. But even so you still should take that diaphragm off (3 screws) while it's opened up as it will be just too vulnerable sitting on that huge magnet to any small bits of metal getting close. Cannot stress enough to keep the work area completely clear of any ferrous bits... Take care in there!
Yeah, I'll definitely unscrew the leads to the cap. Good tip!
 
Actually, after looking at the pictures I taken when I pulled my LE85's apart it looks like it could possibly have been safer for me to pull the other end of the jumpers that go to the binding posts instead of how I did it in order to replace the foam.


While they are silver in color, the horseshoe clips are ferrous! As soon as you loosen those screws and remove the horseshoe clip, it will instantly be attracted to the magnet via the dome of the diaphragm and will leave marks on the diaphragm! (They often look like vampire bites.) You must be mindfull and have the wires well in hand when loosening those screws and keep the clips away from the diaphragm.

Also, if at all possible, do not use a ferrous screwdriver. Again, just looking for trouble.
 

While they are silver in color, the horseshoe clips are ferrous! As soon as you loosen those screws and remove the horseshoe clip, it will instantly be attracted to the magnet via the dome of the diaphragm and will leave marks on the diaphragm! (They often look like vampire bites.) You must be mindfull and have the wires well in hand when loosening those screws and keep the clips away from the diaphragm.

Also, if at all possible, do not use a ferrous screwdriver. Again, just looking for trouble.
Thanks for this info! I think I would only remove them from the cap as that's what needs cleaning and new foam glued to.
 
Thanks for this info! I think I would only remove them from the cap as that's what needs cleaning and new foam glued to.
Just tape those leads off all the same, use non ferrous screwdriver, and get the screws out of the area...You'll be fine..
 
Thanks for this info! I think I would only remove them from the cap as that's what needs cleaning and new foam glued to.


Here's one on a 4435 with the dreaded vampire bites I was alluding too.

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