Refurbishing 40mm Cardo Helmet Speakers

Cardo HD Speakers

I’ve had the Cardo Freecom 4X for about two and a half years, which means I’ve had the current 40mm JPL helmet speakers in my Arai Astro GX helmet for almost two and a half years too. However, the speakers were in a bit of a sorry state. Almost as sorry as the fact that I didn’t take any photos of the process described in this post. Oops. This one will have to be theatre of the mind I’m afraid.

These speaker units remind me of those headphones which came with Walkmans and the other personal stereos in the 1980s. Giving my age away there a bit.

After those two and a half years, the foam on the front of the speakers was ripping away – they were held on by a gummy adhesive to a metal frame which protects the speaker coil and drivers themselves. This left that metal exposed so there was even some rust which I suspect is a by-product of my sweaty ears.

On the rear, the foam wraps around and then on top of that is a velcro seal which sticks to the back of the speaker unit and the foam, holding it all together. That velcro then attaches to the other side of the velco in the helmet. You know what I mean.

First then I removed that velcro seal, pulled all the stuck foam off, then cleaned off the remainder of the original adhesive with a combination of scientifically rubbing it with my finger, and cleaning it with citrus cleaner and isopropyl alcohol.

Next was peeling off what was left of the foam from the speaker unit and protective grille – not difficult – then cleaning the old adhesive off the same way.

As for the small amount of rust on one of the speakers, I got some 600 grit sandpaper and gently sanded the rust off, being careful to wipe the residue off, and blow the rest outwith a small hand blower I got years ago for my old dSLR and which I’d completely forgotten about until I was about to use a can of compressed air…

So both old speaker units were now cleaned.

Next I put on the two new 40mm foams on I’d carefully selected on Amazon Japan. The foam was plesently smooth actually and went on with a nice, snug fit. I was concerned they’d be too tight, or too loose, but no, they went on really well. It’s worth noting that I did not apply any kind of adhesive to the protective grille this time, which is why I was concerned they’d be loose and cause a problem when taking the helmet on and off.

So far so good.

Next I applied a few strips of strong but thin double sided tape to the inward (non velcro) side of the the velco pad, which then was stuck down to the wrapped around foam and the metal back of the speaker coil, giving a pretty strong bond.

After doing both speakers, I let them settle overnight then stuck them back in the helmet and yes – success! Sound quality was back to normal, they look new again and it’s smoother taking the helmet on and off.

I had all the stuff I needed except the foams, which were 475yen for 4, so for this fix it was ~240yen for these two. The tape was 750yen for 20m which I bought a while back to affix some sound dampening panels to the washing machine cubby (a long story) – it’s strong and also very thin.

Given a new set of speakers from Cardo costs 55USD – about 8,600JPY with today’s rubbish FX from Japan – this refurb saved me a lot of money and even if I have to do it again I still have 2 foams left.

To be fair, since Cardo uses standard 3.5mm jack for their speakers, you can find 3rd party speakers which would likely save you money too, but I still like my refurb. Not all communicator companies allow you to easily use other people’s speakers.

So there we have it – nice clean speakers sliding over my ears…mmm…like new sheets on a bed. Or something.

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