Bang & Olufsen Beovox S45 speaker re-foaming

I got hold of this pair of Beovox S45 speakers just before they ended up in the dump. They were in 'apparently' excellent condition, until I took off the grills and found that the foam surrounds on the woofers were completely rotten through.
I found re-foaming kits for this model of speakers from a company in Germany, called Lautsprecher Technik:
lautsprecher-technik.com
They ended up offering me the kit if I agreed to let them use my video on their website as an Instructional aid. I agreed, and here we are.
I hope you get inspired to try this yourself if you ever need to give speakers a new lease on life.
Enjoy.
You can now support the channel:
/ mcaldeira paypal.me/macaldeira
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[@trumpetRex]

This is the best, most informative video instruction of a refurbishing of a speaker that I have yet seen on KZbin. Excellent guide for all who are tempted to do their own work. Thank you.

[@electronicsoldandnew]

Thanks

[@Chris-ng5sy]

Great video and thanks for showing us- have ordered exactly same to do mine

[@electronicsoldandnew]

👍

[@chairuser4]

Those are legendary, beautiful

[@electronicsoldandnew]

I like the clean lines.

[@andybbeck2043]

Great you find these and saved them. Great video content as allways .when i go to las palmas its amazing some stuff thrown away at side of big bins .great video Manuel

[@electronicsoldandnew]

Unfortunately we live in a “throw away” society. I prefer to give these things new life. The problem is usually that new crap costs less than fixing something vintage, so people just go with the flow.

[@neildavidson3513]

Great video. Just repaired my Beovox S55’s and they sound great again. Hopefully they’ll last another 40 years 👍

[@electronicsoldandnew]

👍

[@edwardbalboa5528]

Yes..but you won't !!

[@keithburnett-i7f]

Thank you for the video 👍

[@electronicsoldandnew]

my pleasure

[@jamesmcghee1225]

Great video & very informative thank you 😅

[@electronicsoldandnew]

Pleasure

[@Daijyobanai]

I bought the kit for a set of Beovox S80.2 speakers after watching this video, also from Lautsprecher Technik in Germany who provided the kit used here. I probably would not have undertaken this without this video, I certainly would not have bought the speakers, knowing that the foam on these 35-40 year cones would be in bad shape. Having this video and being able to see the process is what decided me on undertaking the repair. So, thank you to Mr. Caldeira and 'loudspeaker technical'. I now have a pair of new sounding S80.2 Beovox after just a couple hours of pottering about. Also, if you order a kit, I can recommend the glue remover they sell with it as an extra, it really makes the job even easier, getting all the gunk from the cone frames. The only negative was the Norwegian taxes on import! I'm now considering getting another kit for some speakers that cannot be replaced, but might be fixed by re-foaming. Recommended!

[@electronicsoldandnew]

It’s great to know that. Thanks for sharing your experience.

[@maidiac4607]

Excellent video - I only have one comment… When reassembling anything with selftapping screws, always start with a hand-screwdriver and rotate it counterclockwise until you feel the screw slightly dropping down. This way you are at the start of the original threat, instead of forcing a new one (witch wil weaken the plastic, and after several undos and redos will leave a smooth hole witn no threat at all).

[@electronicsoldandnew]

True. I failed to follow one of my own rules.

[@danielsaturnino5715]

I have a pair of celestion speakers with woofers in that sad state. Maybe I should give that a try. Thanks for sharing.

[@electronicsoldandnew]

You should. It’s quite easy.

[@erwinrauschendorfer5747]

When I have replaced the surrounds on speakers I use my power supply to apply a dc voltage and raise the speaker cone a bit to give me clearance to apply glue to the frame without having to pull the cone out of the way. I can then also use it pull the new surround evenly into the glue. Assuming the existing voice could and suspension are aligned properly, there is less risk of pulling the speaker cone out of alignment. This has allowed me to avoid removing the dust cap and shimming the voice coil. I’ve used this method successfully on a dozen or so speakers I’ve rebuilt.

[@electronicsoldandnew]

That’s a great idea. Hadn’t thought of that, but definitely going to give it a go in future. Thanks

[@jims2667]

Interesting that you can get away without shimming the voicecoil on some speakers - I've only done a few, all 50's or earlier speakers with very small gaps, but in each case I had to shim them &/or adjust/repair the spiders to get them centred. Also, it's absolutely terrifying the first time you do one and it seems the surround will keep wrinkling up and never stick down properly! I watched many videos before I did my first one, and none of them mentioned that! Congrats & thank you for showing that it does settle down as it dries 😜👍

[@electronicsoldandnew]

I must admit that I also believed that the shimming was obligatory. However, thinking about it, even the slightest “pull” from the foam in one direction can cause the coil to scrape even when you have the shims in there, when you remove them. This worked very well, but I must admit that the first one I did caused some stress. The glue dries pretty quickly and you get into a panic wondering if it’ll still move as you need it to when the drying starts to impede the foam from shifting. I’ve missed your comments, by the way. Thanks for being back :)

[@stintus1]

The spider would keep it aligned, don’t really need shimming

[@jims2667]

@@electronicsoldandnew I don't think it's so much the centring as the angle - though, thinking more about it, getting that right is probably (and, going by their instructions, seemingly in practice) easier with lighter plastic/plasticised cones, accordion spiders, and the old glue line to guide when locating the new surround. The ones I did that I know definitely needed to be shimmed were heavy paper cones with integral surrounds that had to be cut away (so no glue line to follow) and rear "3 legged spider" spiders. Those spiders at least don't do much to prevent the cone tilting - once the surround is gone, the cone tips easily from side to side under its own weight - so the voicecoil needs shimming to be centred & run true. Thanks for the kind words of (re-)welcome 😉 - real life's been a bit preoccupied recently, though I have been watching and 👍ing your videos. Enjoying the latest Braun repair, and looking forward to the next instalment!

[@schraubnix1583]

Hello For removing old foam and glue from the speaker frame it works too when you use a eraser , in german its called Radiergummi . :-) fine job , thumbs up greets Uli

[@electronicsoldandnew]

That’s a good idea. It will hurt the fingers a lot less :)

[@lyntonprescott3412]

Great stuff. Well done. Watch out for that cat, looks vicious lol. Could do with you over here, started work on my Hallicrafters Sky Champion today and scratching my head already!

[@electronicsoldandnew]

I’m not surprised. It is rather an interesting story set.

[@Mr.-Wint]

A huge improvement, - and surprise, - that the center cap don't have to be removed for voice coil alignment !

[@electronicsoldandnew]

👍

[@zerosanity01986]

Bem executado bom trabalho. Uma das coisas que uso e facilita o trabalho é uma base rotativa, daquelas do Ikea de cozinha. Ainda não tive a sorte de encontrar nada de jeito que tenha sido deitado fora. Mas concordo consigo que vivemos numa sociedade consumista e com mentalidade do deita-fora-compra-novo...

[@electronicsoldandnew]

Obrigado. Já pensei comprar uma dessas tábuas, mas não temos IKEA aqui na madeira, e cada vez que vou a Lisboa não me lembro disso.

[@svendtveskg5719]

Thank you, thank you, thank you! And, by the way: THANK YOU. :-)

[@electronicsoldandnew]

I guess you have some speakers to refoam :)

[@svendtveskg5719]

@@electronicsoldandnew Yes. :-D Beovox S80'es, kit already ordered. A true gem, that store.

[@Plekteret04]

As Sean said at simplyspeakers, its usually not necessery to remove the dustcap. The cone and the coil will naturally move into center of the the gap when moveing the cone up and down. Can be adusted during glueing too. He hus rubbing alcohol to clean edges.

[@electronicsoldandnew]

👍

[@davidhollfelder9940]

Nice job. You could have used your turntable (Lazy Susan) to work on your speaker. You can use some double sticky back foam tape, stuck to the turn table, to hold the speaker centered.

[@rodneybrand8521]

Finally..someone who goes it to detail on how to repair the foam..now if only i could find the repair foam.. Excellent job..just wish you would let us hear them perform..Cheers 🍻🍻🍻🇺🇸🇺🇸🇺🇸

[@beingsneaky]

amazon sells speaker repair kits.. and another place is Parts express www.parts-express.com/Search.aspx?keyword=refoam%20kit&sitesearch=true

[@electronicsoldandnew]

Should be quite easy to find them in the States. Here in Madeira, it’s impossible, so I usually order stuff from Germany.

[@mr.strother]

Also in the US-were you able to find a good replacement? Hoping to tackle soon but shipping to US from the suggested seller is 2x the price of the item. Just finding Chinese clones that are slightly off…

[@alanthomson7770]

So impressed by your video I sent for kit for my S50s , but non of my screwdrivers fit . What crosshead do you use to remove screws .

[@electronicsoldandnew]

Not really sure. It’s been a while.

[@MichaelBeeny]

When choosing a new pair of loudspeakers always choose a pair with a rubber or neoprene surrounds. Foam ones always fail, some sooner than others.

[@electronicsoldandnew]

True. These things are a restoration waiting to happen.

[@geraldmcmullon2465]

Refoam bass units may have mixed results. I re-foamed a pair of CX100 and had to add an additional foam ring to stop the edge vibration. The contact glue was unforgiving to re-centre. It might be possible to remove them and try with another pair of foams but the padding I used seem to have worked and a big improvement to my how they were. When I first set them up at low volume they were fine. I put the volume up high and the original foam surround - without grills - broke up and shot across the room. I tried the same on a pair of speakers for a car with less success. They still have edge vibrations. As I had already sourced replacement bass units I have not attempted a further fix.

[@electronicsoldandnew]

I think the glue is essential. These have worked perfectly so far.

[@rickwise9910]

Very nice! How long did it take in actual time?

[@electronicsoldandnew]

Probably about an hour each.

[@rickwise9910]

Thank you, sir: I like to have a sense of what I'm tackling when I start this kind of thing.

[@mrdeexxx]

Hi what is the name of the blue that you're using thanks by the way great video

[@electronicsoldandnew]

The glue came with the re-coning kit. Not sure what it is exactly.

[@mrdeexxx]

@@electronicsoldandnew ok thanks for the reply

[@ryanmorrow2058]

Do you do any amplifier design work. Like redesigning a vas stage to go from a bjt to tubes. Is that something you do.

[@electronicsoldandnew]

Not really. I’ve done things like that for my own personal interest, but I don’t do it as a job.

[@ryanmorrow2058]

Ok thanks

[@kennethiman2691]

Shouldn't you replace the crossover capacitors? I use painters tape to hold down the curling until dry. Great video as always.

[@electronicsoldandnew]

I haven’t, but after listening to them I may just do that.

[@irfhanmirza878]

@@electronicsoldandnew In terms of Crossover Capacitor is there a particular quality we should stick too?

[@electronicsoldandnew]

Irfhan Mirza : medium. No need to spend fortunes as the result will be negligible.

[@alfredneumann4692]

Super. Do you hear a difference between the re-foamed and the original speaker? And it's true, normally i would buy a new speaker, which would fit into the hole. But re-foam it.... brrrrrr never came to such an idea. But now....... perhaps the next problem will come and then i will remember. Thank you for showing us this experience.

[@electronicsoldandnew]

The originals were not tested at all because the foam was completely rotten. They sound good now, but I am considering looking at the capacitor in the “cross-over” as it probably needs replacing.

[@alfredneumann4692]

@@electronicsoldandnew Ah, ok, of course, the c in the frequenzweiche should be checked. Can't wait for your next video.

[@Michlag]

Oh! What do I hear at 8:33 ? :D

[@electronicsoldandnew]

Yep. He’s dying to become famous :)

[@beingsneaky]

i cn see why some otehr person i watched has a turn table?? lazy susan?? to place the speaker on. makes turning of it easier.

[@electronicsoldandnew]

It does make things easier :)

[@XtremeKremaTor]

Disliked cause you didn't show the inside of the speaker. I'm fussy like that

[@jonka1]

Pity you take yourself so seriously. Not a recipe for a satisfying life.

[@Vingul]

Very entitled!