JBL. 044-1 Tweeter Driver Dampening Foam Replacement

[Stoddrob]

I purchased a set of JBL 044-1 tweeters (inexpensive) to try the process of replacing dampening foam before I ever attempt to do it on a set of 044ti tweeters. Same process. The only difference is the tweeter dome is titanium. This is also the same process for the 044 tweeter. The JBL 044-1 was used in the original JBL 250 four way speakers. They upgraded to the titanium domed tweeter for the ti series speakers that included the rebranded JBL 250ti.

First you have to get the mesh screen off the housing to remove the screws to get the driver out of the housing unit. That is a pain. I have done this on a bunch of 044ti tweeters and 035ti tweeters. This one gave me a hard time. But eventually the rubber gasket came out without TOO much damage to the housing and or the mesh screen cover.

Then I removed the four screws using 3/32 hex. Caution — the screws are magnetic and they will get away from you and strike the dome and dent it. Hold onto them good when removing them! these had a layer of rust….so I treated them and will repaint the screw heads.

After removing the last screw, t driver then just falls out from the housing (be aware). Be sure to mark or identify the positive side of the voice coil and dome gasket. There is a notch in the gasket where it lines-up with the housing. Mark it so as well you know how it goes back on with the positive terminal towards the marked positive side of the inside of the housing.

Now for some patience. You have to use some “tools” to try to pry the gasket with the voice coil and dome off the magnet. you have to lift all around. JBL used an adhesive that doesn’t come off so easily (it looks like contact cement to me). Here’s an image. BE CAREFUL NOT TO INSERT your prying tools too far! You will damage the voice coil. It should be apparent. There are four screw holes…just don’t go in too much beyond them. I tried to put these “tools” in and let the pressure on the gasket lift it off overnight. Didn’t work. I came back the next morning and used a hair dryer to warm things up and then started pushing down on my “tools” to lift the gasket with the voice coil and dome up. Eventually it started to give way and finally popped up. You have to go slow and be patience. Don’t be in a hurry. This is the critical step in success or failure.

I was shocked to see that the dampening foam was in excellent condition! It measures 3/4 inch diameter by 3/8 inch in height. Either someone replaced the foam or the speakers were hardly used. Or the tweeters were replaced and the speakers were upgraded a long time ago to make them a ti series speaker. I decided to leave the dampening foam. I have new foam and a foam cutter to make new ones…but there was absolutely no need. The foam will work just fine.

So I cleaned-up the adhesive with alcohol and cleaned out the voice coil cavity (be sure not to get any debris in the cavity when cleaning) pushing the old adhesive out away from the cavity. I dropped a thin line of contact cement in the same place the old adhesive was on the magnet and the gasket. NOT TOO MUCH! You don’t want it to spread and reach the voice coil and cavity!

I also used a little contact cement in the center for the dampening foam…and a little on the dampening foam. Pushed the foam in place (centered).

I lined things up (notch, screw holes using the screws, positive connector in the correct direction) and pressed the two components together making sure I was centered over the dampening foam and the voice coil centered into the cavity. Alignment of the voice might best be done with a sweep generator but to be honest, if the notch is in alignment and the screw holes are all aligned with the screws inserted, it should be in the exact same position as it was when it came off. I’m no sure there’s much room for error.

The next step would be reinstall the driver in the housing, secure with the screws, and replace the mesh screen. You can reinstall the rubber gasket, or find the material to make a new one the same diameter. Or go without — the magnetic force of the magnet will actually hold it in place.

It’s not rocket science…but I was always too timid to try this on my 044ti tweeters. I paid someone else to do it — and waited two months to get them back. I really don’t want to do that again so I used this purchase as a training expense. Worked out great!