View Full Version : Recently aquired 4310's

04-12-2009, 08:45 AM
New to this forum and first time poster.

I recently acquired a pair of 4310WX Control Monitor's - my first pair of JBL speakers. The drivers in both are in excellent condition and functioning properly. Attached is a pic of one of them. The cabs however, are a bit rough and both have damage to the lower right front corner. Right now I am just enjoying listening to them but would eventually like to repair the cabinet damage and possibly recap them. The latter is where I need some advice and information. I have searched pretty extensively but have been unable to come up with a crossover schematic. Apparently the speakers are too old for such a document to be available which seems a bit puzzling to me if it is considered a classic. Could someone please point me to a site where even a hand drawn schematic might be available? Also, since the mid and high L-pads are on the bottom of the speaker, I am wondering if the entire crossover is also located there with access through the woofer opening, or more likely might it be mounted on the inside/rear of the cabinet opposite the speaker terminals where it would be easier to access with a straight shot through the woofer opening? And finally as to advisability. I have recapped a number of other speakers, mostly vintage Infinity's, but was wondering if recapping the 4310's will somehow diminish their historic value. I am not concerned about resale value as it is not my intent to sell them, but just whether or not, since they are fully functional, they should be kept in their "original" form.

Finally, is there an easy way to DeOxit the L-pads without taking everything apart? They are a bit scratchy.

Thanks in advance for whatever information and/or advice anyone is willing to provide.

04-12-2009, 06:01 PM
Referring to:


then here (for late model 4310 with 2122 driver):


Someone else might be able to tell you if there were network differences for the earlier model.

Note that the link from here:


is misdirected to 3110 network, and should be fixed at jblproservice.com.

04-13-2009, 09:05 AM
Thanks for both of those leads. I actually managed to find that 3111 schematic on my own but only after hours and hours of researching. I also found info on the L100 crossover upgrade that sounds interesting but I think I'd rather leave my 4310's in "stock" condition.

I am picking up another 4310 (single) with a trashed cab next weekend on which to experiment with removing drivers, accessing the crossover, and cleaning the L-Pads and all such without risking my "good" speakers so that should be entertaining and informative. It will also provide me with a set of good spare drivers.

Again, thanks for your help.

04-13-2009, 10:19 AM
Cleaning L-pads is akin to patching tires... They will probably work for awhile.
For all the work needed to access them, especially if the plan is to keep the speakers,
I'd humbly recommend replacing them. Nice that you have a junker to tinker with first.

If the 4310 logo/control panel is similar to other JBL monitors, you might want to
have a hair dryer or heat gun ready, to soften the adhesive. There are other threads
here that go into various experiences in removing the drivers
(ranging from 'no problem' to 'where's the sledgehammer?').

04-13-2009, 04:57 PM
I read yesterday about removing the foils - I can't remember the exact term - with a har dryer and that doing so may or may not reveal screws that hold the L-pads in place. One of these foils is already loose on the side with the L-pads but I think I will reserve my digging, at least for the time being, to the extra speaker I am picking up on Saturday. Once I've gained a little knowledge and confidence, I'll see about working on the "good" 4310's. In the meantime, I'll enjoy listening to them in my small home office which is perfect for such near-field monitors. Heck, I even managed to get them 4' off the ground by using a pair of Infinity Monitor IIa's as stands.with a set of Auralex foam bases between, and they sound pretty good if I do say so, although I did have to crank both L-pads on both speakers as far to the left as they would go.

04-13-2009, 06:54 PM
Cool. Those drivers appear to be in very good cosmetic condition.
It'll be interesting to see how your cabinet refinishing comes along.