Repairing a Broken Pair of Boston HD-5 Speakers

A couple weeks ago, I started noticing weird sounds coming from my stereo speakers. The long, low tones that score tense scenes in movies like It Follows and Hush (both highly recommended) were full of pops and cracks that seemed all wrong. This particular pair of Boston HD-5s I got for free from a family friend, and they sound better than free yard sale speakers have any business sounding, so I want to keep them around as long as possible. I opened them up to see if anything was obviously wrong, and this is what I found:


At first I thought the cones were completely shredded and figured I would be dropping significant money on replacements, but some Google searches on DIY speaker repair led me to Simply Speakers. I learned that, thankfully, my cones weren’t broken. The foam between the speaker cone and frame degrades over time, so this is a common problem in old speakers. The even better news: It’s an easy fix.

Simply Speakers sells foam repair kits for every size and brand of speaker imaginable, and a Boston 5.25″ kit was only $25. Much better than a new set of speakers.

The first step of the repair was to remove the speakers from the cabinets and clean the old foam off. Some of it had chipped and fallen into the cabs, and a few remaining large pieces were easy to pull away, but the foam that was still glued to the edge of the cones and and frames was more challenging. After a lot of careful scraping, I felt like they were at a point where the new foam could be glued on smoothly.

Gluing the new foam on is pretty straightforward, but it’s important to keep the cone aligned directly in the center of the frame (a second set of hands helps – thanks Liesi!), or you’ll end up with worse sounds than you had before. It took a little trial and error for us to get the first speaker right, but the second one came out very clean. Take a look:


I ran some test tones through the speakers after the glue was completely dried with no issues. After a couple weeks of TV and music through them every day, I’m completely satisfied with the fix and looking forward to using these speakers for the foreseeable future.