• Please note that Audiokarma will be offline briefly for updates early on Monday morning, September 28th.

JBL L80T Project -- Gone Wrong

Really nice looking speakers - kudos on your thorough work -
sounds like your persistence paid off!
 
Thanks, all! Yeah, this project was kind of two steps forward one back the whole way: I ruined both tweeters by trying to replace their foam dampers; got another pair on eBay and the seller dropped and broke one; got a second pair on eBay and used them.

I refoamed the woofers but one of them had crud in the gap; got another pair from brainsmasher.

One midrange had a wrinkled surround so I found another on eBay.

The veneer was chipping so I repaired it here and there.

One grill frame had a crack in it so I fixed it. The cloth had holes so I'm replacing it.

Some of the feet were missing and the plinths were a little tired looking so I removed, patched, replaced and repainted them.

I replaced the crossovers with T3s and recapped them.

And I oiled the cabinets.

Other than that, the project was easy! :D
 
And finally, in situ, in my son's room:

DSC_3197.jpg
 
Well ya went through a bit of work, but it paid off nicely! Ever find out what the issue was with the scrapin woofer?
DC
 
You know, I never did fix it. This project left me with: Three broken 035Ti / TiA tweeters, one working 104-H2 midrange with a wrinkled surround, two working woofers (including one with that foam rubbing sound), two L80T crossovers, and two rear terminal plates. :sigh: I may cobble together another speaker or some eWaves out of this mess. :D
 
MEK to the rescue

MEK will dissolve the Bostik adhesive JBL used to bind the cone assembly to the frame, including the spider. Paint it on the glue joint with an acid brush. It will take several "coats" and more than a few minutes for the solvent to work. A piece of 1/4" wooden dowel, sharpened to a wedge at one end, can be used to scrape at the glue and GENTLY pry the spider from the frame, once the adhesive is soft. Definitely do all this in a well ventilated space. Likewise, the dust domes on old JBLs can be removed without damaging them, or the cone, by softening the glue with MEK, using a similar process.

Once the cone assembly is removed, check the coil and form for obvious damage or lack of roundness. Clean the gap by wrapping some adhesive tape inside out on a thin piece of stiff flat plastic, such as half of a playing card, and working the adhesive tape around in the gap.

This is how we do it in our JBL authorized speaker shop. If your coils are damaged, or you have an accident with the cones that trashes them, you can send the woofers to us, or any other authorized JBL service center, where they can be restored to original operating condition by the installation of a JBL kit (yes, kits are still available for the 127A!).

Ton Garson
Aural Technology, Ashland, Or
 
I am very glad you got these going again. I must say that you sent me a bit more $ than I asked for. I will get even next time.
 
tgarson said:
MEK will dissolve the Bostik adhesive JBL used to bind the cone assembly to the frame, including the spider. Paint it on the glue joint with an acid brush. It will take several "coats" and more than a few minutes for the solvent to work. A piece of 1/4" wooden dowel, sharpened to a wedge at one end, can be used to scrape at the glue and GENTLY pry the spider from the frame, once the adhesive is soft. Definitely do all this in a well ventilated space. Likewise, the dust domes on old JBLs can be removed without damaging them, or the cone, by softening the glue with MEK, using a similar process.

Once the cone assembly is removed, check the coil and form for obvious damage or lack of roundness. Clean the gap by wrapping some adhesive tape inside out on a thin piece of stiff flat plastic, such as half of a playing card, and working the adhesive tape around in the gap.

This is how we do it in our JBL authorized speaker shop. If your coils are damaged, or you have an accident with the cones that trashes them, you can send the woofers to us, or any other authorized JBL service center, where they can be restored to original operating condition by the installation of a JBL kit (yes, kits are still available for the 127A!).

Ton Garson
Aural Technology, Ashland, Or
Click to expand...

Great bit of information, thanks for sharing.
 
Nice work!
"Other than that, the project was easy", Uh huh.

One more thing, is your son still in a crib? That is the cleanest looking kid's room I've seen in a long time. Tell the boy he's doing good.
 
Heh, thanks. (And thanks again, Brainsmasher!) He's 15, and a great guy. I did tidy up a teeny bit (I hate cluttered photos) but he was already 90% there.
 
Looking good! I had some L80T3's. They were really nice sounding. Also, they are nice in that they aren't "huge" (compared to a L150), kind of a happy medium between a L100 and L150.

I sure do like the darker color better, I had the light oak or whatever it's called.
 
Thanks! Yeah, I have L250s with 250Ti guts in my living room, and the L80Ts sound to me "thinner" with less lower midrange and bass, but in my son's smaller room they are perfect. He's delighted with them and thinks they sound much better than the L40s that he had in there before.
 
Do you think these are the "spaghetti veneer" JBLs I've seen mentioned on this forum, where supposedly JBL used a thin layer of "veneer" made from wood pulp with grain dyed or printed onto it?
 
You must log in or register to reply here.
Back
Top Bottom