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jan_slagman
05-01-2008, 12:56 PM
Hi Friends,

Lately i acquired a pair of JBL L110 loudspeakers. Every component works
satisfying except the controls for the mid-and high frequencies.
They only work at the highest level and that is too much. What can one do to solve this problem ? What are the specifications of these L-pads ? Please let me have your comments.

With kind regards,

Jan Slagman
The Netherlands

LRBacon
05-01-2008, 03:31 PM
Hi Jan,

They may be dirty or corroded, but from what you have said it sounds like they may be open. Try turning them rapidly from minimum to maximum several times. It seems unusual for all four of them to be bad.
I have several pairs of L110's and a couple of the N110(A) networks and none have had bad L-Pads.

Have you tried cleaning them with some type of fader lube-deoxidizer- cleaner?

To access them first place the speaker on it's back. Remove the woofer. Remove the plastic indicator (which surrounds the adjustment knob) by slipping a flat blade knife gently underneath and lift up slightly to break the glue holding it in place. They can be glued back in place. Now the shaft extension knob can be pulled straight off with a pair of pliers. You can then use needle nose pliers (unless you have the proper socket wrench) to unscrew the nut on the threaded portion of the shaft. There should be a washer underneath the nut. Once the nut is loose the L-Pad will be free of the front baffle and be accessible through the hole for the woofer. The wiring to them is together, so both will have to be free to easily access them. Try spraying some the deoxidizer-cleaner through the holes in the back side of the L-Pads and turn the shafts from minimum to maximum several times.

When you put them back together, I think the L-Pad that has white paint on the shaft side is for the midrange. Hope this helps.

Larry

jan_slagman
05-01-2008, 04:24 PM
Hi Jan,

They may be dirty or corroded, but from what you have said it sounds like they may be open. Try turning them rapidly from minimum to maximum several times. It seems unusual for all four of them to be bad.
I have several pairs of L110's and a couple of the N110(A) networks and none have had bad L-Pads.

Have you tried cleaning them with some type of fader lube-deoxidizer- cleaner?

To access them first place the speaker on it's back. Remove the woofer. Remove the plastic indicator (which surrounds the adjustment knob) by slipping a flat blade knife gently underneath and lift up slightly to break the glue holding it in place. They can be glued back in place. Now the shaft extension knob can be pulled straight off with a pair of pliers. You can then use needle nose pliers (unless you have the proper socket wrench) to unscrew the nut on the threaded portion of the shaft. There should be a washer underneath the nut. Once the nut is loose the L-Pad will be free of the front baffle and be accessible through the hole for the woofer. The wiring to them is together, so both will have to be free to easily access them. Try spraying some the deoxidizer-cleaner through the holes in the back side of the L-Pads and turn the shafts from minimum to maximum several times.

When you put them back together, I think the L-Pad that has white paint on the shaft side is for the midrange. Hope this helps.

Larry

Thanks Larry,

I have download the manual tonight and i have read it. I recognise what you say. I don't have to remove a plastic indicator, for there is no indicator and no adjustment knob. I am looking directly at the shafts of the attenuators for the mid-and high controls. I will change that later !!!
I will follow your advice ! Can these L-pads be replaced when needed ? Can they still be obtained from JBL ?
Well first i will try it the way you told me and maybe it's a piece of cake.
Thanks again for your kindness to help me in this matter.

With kind regards,

Jan Slagman
The Netherlands.

LRBacon
05-01-2008, 05:25 PM
I recognise what you say. I don't have to remove a plastic indicator, for there is no indicator and no adjustment knob. I am looking directly at the shafts of the attenuators for the mid-and high controls. I will change that later !!!
I will follow your advice ! Can these L-pads be replaced when needed ? Can they still be obtained from JBL ?
Well first i will try it the way you told me and maybe it's a piece of cake.
Thanks again for your kindness to help me in this matter.

With kind regards,

Jan Slagman
The Netherlands.

They may be replaced with something similar, they are an 8 ohm L-Pad with 3 wires each from the network soldered to their 3 terminals each in each speaker.

You may have a problem finding ones with the same shaft length. I don't think JBL still stocks them from what I've gathered here on the forum.

I have four that are still attached to their networks. I know that 2 of them are good and I can check the other 2. I probably won't be using them since I have already been using the networks for parts. If I put anymore L110's together they will be L110A's. I could send them to you if your L-Pads are defective. You can PM if you would like to.

Larry

Mannermusic
05-02-2008, 05:50 AM
Here in the mid US we get the L-pads from Parts Express in Dayton, Ohio. 8 ohm, 15 watt, 1" shaft: PN 260-250. $4.50 ea. www.parts-express.com. To repair 'em, I've found you've got to remove the tin cover and brush the coils and wiper with liquid "Deoxit." But, there has got to be sources over there - it would be a professional audio supply store of some sort. Mike

jan_slagman
05-02-2008, 09:45 AM
Thanks friends,

I really appreciate your help. Thanks for your professional advice.
I think i know what to do.

Kind regards,

jan Slagman
The Netherlands