We recently bought a new TV (a Vizio M370nv — a very nice unit), and in a classic case of “one thing leading to another,” I found myself performing surgery on my JBL J520M home theatre speakers.

The new TV doesn’t have the most powerful built-in sound system, but when it’s connected to my home theatre– which hadn’t really been used in many years– it sounds wonderful. It was during a scene in Master and Commander that I heard a buzzing in the left channel, and I pulled the grille off the speaker to see that the foam around the speaker’s edge had deteriorated very badly. (The movie’s audio scared the daylights out of the cats, though.) I inspected the right speaker and found similar deterioration, but not enough to cause buzzing yet. I bought these speakers in 1995, so they’ve been in service for a while.

I looked up “speaker repair” and my model number, and I found an outfit called Simply Speakers who sells repair kits for my speakers along with online instructions for making the repair. The kit cost about $25 and showed up very quickly– just a couple days.

It was a time-consuming process, as there’s an amount of scraping, wiping, gluing, and waiting involved, but in the end I had two great sounding speakers. Best of all, I didn’t have to start dealing with home-theatre salespeople.

I took some photos during the repair process which you can see on the next page, along with some comments.

If you find yourself in a similar situation, you might want to check out this solution. Time to scare the cats again.

Speaker unit.

Speaker unit with grille removed.

You can see the deterioration around the perimeter of the woofer. This is actually the right channel speaker, which wasn’t as bad as the left. I’d already completed the repair on the other speaker before I decided to document the process– just in case I botched the job. 🙂

Removal. This is a JBL P20G woofer for those of you who were wondering (or Googling). I was surprised to see this driver was made in the USA.

Ready for surgery. The paper plate was a great “stage” to perform this work, because the old foam got really nasty and sticky as I was cleaning it, so replacing the plate gave me a new cleaning surface whenever I needed it.

This is the replacement foam.

These are the tools I used: X-Acto knife, Stanley knife, acetone, rubbing alcohol, and Q-Tips and paper towels (not shown). The kit also includes glue for the job, which reminded me a lot of model glue. Note the cup of Biggby coffee in the background– it helped. 🙂

Foam removal. Much of it came off by gently using my fingers, but it made a mess as it was disintegrating on contact. A light touch with the X-Acto got the more stubborn pieces off.

Final cleaning. The instructions recommend using rubbing alcohol, but I became a huge fan of acetone during my days working in an electronics assembly plant. It took a few minutes, but it helped in removing all the residue.

Ready for re-foaming.

The new foam, partially glued in place. After a couple hours’ drying I reinstalled the speaker into the cabinet and we were back in business!

Thanks again to Simply Speakers for a great product, easy-to-follow instructions, and fast delivery! (This is an unsolicited testimonial: I was not compensated in any way– I’m just a satisfied customer.)