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View Full Version : Bad pots on L65 Jubal



hklinker
08-29-2009, 09:20 PM
I bought these Jubals new over thirty years ago. I have never been able to adjust the tweeter or midrange without having problems with the pots. If I don't get them just right they drop out.

I tried removing them and using faderlube, with little success. Has anyone else experienced this quirk in the Jubals?

boputnam
08-31-2009, 05:22 PM
There are some posts where users have had (limited?) success cleaning the L-pads. You might search for that, or try and replace them with something comparable from Parts Express (although this is not trivial... :( ).

hklinker
08-31-2009, 08:01 PM
Thanks for the info and the reply to my message! I have re-glued the cover plates on the L-pads so it will be an even bigger job now. Tried Faderlube, but still really touchy, even after ten to fifteen twists. I think they need to be replaced but not sure where to find the right specs so I can order from Parts Express. Any ideas on where to find the specs?

Herb

jcrobso
09-01-2009, 10:19 AM
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-255
Or
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-252
Or
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=260-248

boputnam
09-01-2009, 05:12 PM
Use the 50W for mid and the 15W for the high.
Good one, JC! I told him you'se guys here would come thru with the goods... :applaud:

hklinker
12-18-2009, 03:15 AM
Thanks guys!

Picked up some from Parts Express and not only do they work perfectly, the 2405's sound much better.

Thanks for your help, now on to replacing the caps!

Herb

Mannermusic
12-18-2009, 07:00 AM
I bought these Jubals new over thirty years ago. I have never been able to adjust the tweeter or midrange without having problems with the pots. If I don't get them just right they drop out.

I tried removing them and using faderlube, with little success. Has anyone else experienced this quirk in the Jubals?

I think fader lube is formulated mainly for carbon based controls. Those JBL level controls are wire wound/metal wiper L-pads and they gradually corrode with time (we older guys are experts in this area!). Your new ones will likely do the same thing (I used them in my DIY rig and they lasted about a year). DeoxIT contact cleaner is the necessary chemistry to dissolve the corrosion and also leaves a protective film to retard further corrosion formation. But, it ain't cheap, about $15, and you've gotta remove the cover and get in there with a Q-tip or similar - follow the instructions. I prefer the liquid concentrate rather than the spray so I can get the stuff directly on the coil and wiper, then wipe dry. Best of all, it seems to last - have done a number over the years and have never had a "come back" . . . YET!:blink: Takes some care and effort so the R&R approach is not all bad either. Ultimate solution, fixed L-pads.

jcrobso
12-18-2009, 09:01 AM
Thanks guys!

Picked up some from Parts Express and not only do they work perfectly, the 2405's sound much better.

Thanks for your help, now on to replacing the caps!

Herb
When your ready, check them out.:)