Saturday project: Renovating the B&O RL60
Posted: May 30th, 2009 | Author: admin | Filed under: projects | Tags: auxillary base radiator b & o, b & o rl60 speakers, b&o 60.2, b&o redline, bang and olufsen speakers, projects, redline 60 speaker refoam, refoam abr rl60, rl60, saturday project | 37 Comments »
The wonderful Bang and Olufsen RL60 Speakers
I just bought some Bang and Olufsen Redline 60 speakers from someone in Oakland using Craiglist to replace the tinny, hollow sounding Sony computer speakers next to my PC monitor. They came with a Beomaster 5000 amplifier and a non-working B&O remote control the size and weight of a longer Tom Clancy paperback. It seemed like a pretty good deal for $150 and an hour and half of driving. Not to mention that I had spent all week bargaining him down from his $275 asking price.
I tried them out at his loft in a bad part of Oakland and they sounded good. Just a weird clunking sound when I moved the speaker, which the owner explained was a metal plate. I wasnt’ sure what he meant, but they sounded good and it was a good price. I got the system down the stairs and into the Saab amid some shifty characters lurking in this industrial part of Oakland.
A 50 minute drive home, and I’m still feeling pretty good about the purchase. Naturally, the first thing I do when I get them inside is to take them apart to find the source of the clunk. I discover a loose oval shaped metal place, and a lot of very old brown foam floating around in the speaker’s chassis.
A quick Google and I discover the Beoword.org forums. It turns out the engineers at Bang and Olufsen employed an ABR (Auxillary Base Radiator) when they designed this first version of the speaker. Over time (20+ years now) the foam holding the ABR together disintegrates and prevents the ABR from working.
The project: Find some replacement foam, stick it on to the metal pieces of the ABR and put the speaker back together.
The conclusion: A huge improvement. I’ve replaced the ABR foam on 1 of the 2 speakers and the difference is very noticeable. I think I have the process down to about 45 minutes for the next one, exlcuding the time it take the glue to dry.
Here’s a picture of the new ABR in place, read on for the full process.
Replacement foam in place on the RL60, ready for reasembly.
Here’s the finished result, ready for reassembly. Click below to see the entire process in detail and photos.
Step One:
Take the speaker apart. There are 3 screws on each side, 2 for the straps and 3 further screws within the connections assembly. Be careful with the straps, they may be brittle but should come off easily enough with a little care.
The Bang and Olufsen Redline 60 with ABR
Step Two:
Remove the screws and straps holding the two halves together. Below, the screw holding the wedge which secures 1 of the 2 straps.
The screws behind the B & O Redline 60 speaker
Step Three:
Don’t forget the screw just behind the connections!
Close up of the connections
Step Four:
The inside of the RL60 speaker. On the right you can see the Auxiliary Base Radiator (ABR) which is in rough shape. The foam holding the inside (oval) metal piece to the outer loop had disintegrated. This is the part we’re going to remove, and refoam. The large oval metal piece was clunking around in the speaker and would have eventually come through the outer fabric, not to mention the huge hole hindering the speaker’s acoustic design.
Inside the RL60 speaker. What's left of the ABR on the right.
Step Five:
Remove the ABR by unscrewing the screw on the outer metal loop. The inner piece is loose and can be carefully removed.
A close up of the Auxillary Base Radiator on the RL60
Step Six: Close up of the foam material used. You’ll need to find a replacement as close as possible to this material.
The foam material used by B&O for the RL60
Step Seven: Disintegrating foam after 20+ years of use. I used carpet underlay as a replacement found at Home Depot.
The foam has completely disintegrated and is very brittle after 20+ years.
Step Eight: Remove and clean the foam and glue from the two pieces of the ABR. I used a washing up brush and a knife for the glue.
The two metal pieces of the ABR removed and cleaned up.
Step Nine: Use the outer ABR piece as a template on your replacement foam and cut.
The replacement foam read to be cut
Step Ten: Cut and ready to go. I doubled up on the underlay material to gain thickness.
Replacement foam, ready to go.
Step Eleven: Glue the replacement foam to both metal ABR pieces being careful to space the inside piece equidistant from the outer ring on both sides, top and bottom. I used Liquid Nails to glue the foam underlay material to the metal.
Replacement foam glued to the metal ABR pieces with Liquid Nails
Step Twelve:
Close up of the ABR with replacement foam.
Step Thirteen: Admiring the speaker, and my work.
A view of the speaker half of the RL60 by B&O
Step Fourteen: Replace the insulting foam of the RL60 speaker and screw the back half back on. You’re done!
Replace the insulating foam, and screw the back half back on.
Well done! What a great project and a big thanks for all the excellent photos and the explanation of the work.
Although I don’t think mine need doing (but they are 20 years old!), it may now give me the courage to open them up and possibly do mine!
Thanks again.
Brian, you may have the later version of this speaker, the RL60.2 . These have an updated design, utilizing a plastic base port instead of the foam.
It’s worth checking before you open your speakers up
Great work and a great speaker.
I have an original pair of 60.2′s I purchased new in 1988.
It’s time to fire them up again and enjoy. These are in the permanent collection at the Metropolitan Museum Of Modern Art – real classics.
Enjoyed your info!
I think you have done a nice job considering the materials you have used.
Someone gave me your link and I wanted to see what you did for your Redlines. It makes me proud to see folks restoring older speakers instead of sending them to the landfill. I even had a guy tell me he just cut a board and replaced the ABR with a solid board and loved his speakers!
Keep up your passion my friend,
Mike Cason
WOW! this fix was so worth it! I ended up using a 21lb Barcelona radiant heat carpet underlay and the bass response from these cabinets is WICKED DEEP! I picked up two RL-60′s and a BEOCENTER 2200 for about 100.00 bucks the other day and came across your page while researching the speakers. I had no idea what that “clanking” sound was until I read your blog. Thanks a million for your time and effort!!
Hey Mario – thanks for posting and that was an awesome deal for $100!
Congrats on fixing your speaker – my initial reaction was the same after I bought my RL-60s. Credit goes to Beoworld.org forums for educating me
Oh fantastic! I’ve had a pair of RL 45s for 15 years or so, and only ever used them with a sub as the bass is so poor, soon giving them up as a bad job. After opening them up today to see what has been loose all this time, before ebaying them, I could see something was detached – Your page is the perfect answer!
I’ll be fixing this and keeping them now, can’t wait to hear them!
Thanks for the great page
Thank you for doing this! I couldn’t find a solution anywhere. What foam, exactly, did you use and where did you get it from? I looked back through your article and couldn’t spot it. And, are there alternatives? I heard someone overseas used a rubber membrane of some sort. Thanks!
I used carpet underlay, but I’m sur there are better and worse products out there to use. One idea would be to buy 15″ woofer foam surrounds on eBay and cut them.
Thanks for the reply. Is there a thickness or density – or any other sort of specification – you recommend looking for? I talked to B&O and they no longer have specs. Would like to get close to the original engineering intent. Appreciate it!
I just picked up a pair of these at a thrift store here in San Bernardino ($25.00) today and noticed the same clunking. I opened them up and started searching the net and found your page. I’m off to Home Depot for supplies and I’ll let you know how it goes. Thanks for your page, it was a big help.
Wow, killer deal on some great speakers.
I’d love to see pictures of your restoration, could you take some? Would be great to post them here too for others to get ideas from (with your permission of course).
Thanks
Frank
Great idea I was about the replace with a solid board and a tuned port but I think your way will keep to the original design , I must ad what was B&O thinking , susspending that much steel on thin gage foam , almost a third of the weight of the unit …..thanks for the post
If anyone is interested, I have a pair of RL 60.2 that I purchased new in 1987 and am looking to part ways with them. The information that they are now in MOMA gives me pause, but nonetheless, they are for sale. Please contact me at nick@celebratevitamins.com if interested.
Thanks
Nick
Does anyone know how I can simply get the outer plastic straps and cover repaired/replaced?
I just found a pair of RL 60.2 speakers on the nature strip out the front of some big house, it’s the hard waste collection. These things are awesome. I found this guide and opened mine up, and I found that there were resin tubes instead, maybe they updated the design at some point
Nice find! Yes, in the later version (RL 60.2) they switched from the passive woofer with foam to a port. That means no restoration of the passive woofer is necessary! Enjoy!
Fantástico¡¡¡
He reparado mis altavoces con tus explicaciones y suenan de muerte.
Gracias amigo.
Thanks for sharing your project! I bought a pair of RL60′s for 50 euro and started searching the internet when I discovered the loose plates.
I replaced the foam like you (although the replacement material is a bit different) and they sound great. Thanks a lot again!
Thanks for all this info. I had taken mine apart and found the foam and ABR looking just like yours. Glad you had the courage to lead the way so that I can now attempt this repair.
My instinct tells me the foam is fairly critical, I suppose to allow the resonance to occur and still hold the ABR in place. As you say, you used carpet foam; anyone else find good alternatives?
Thanks again
I agree, the choice of foam material is most important. In hindsight, instead of carpet foam, I may have tried to used the foam speaker surrounds they sell on eBay. You could try to take the largest circular surrounds (15 or 18 inches) and try to make straight sections out of them.
There’s also some Sony speakers (APM series I believe)that have square drivers on which the surrounds go bad. In that case, people have used chamois to mold custom replacement surrounds for. Google would help you find those projects.
This is a service to every RL speaker fan out there! Awesome job!
A cracking article with all the right pics … many thanks. I took my Redlines down off the wall last week … decorating. I heard a clunk … took the other down, and another clunk.
Mine are slightly different from the post. I have a recess, above and below, the square connection area. One screw in each, need to be removed, otherwise it’s identical.
The removal of the back, revealed the same probs. I chose felt and there is good and poor quality. The poor would need doubling, as the article. The good quality is of adequate thickness and I too, used, No Nails. So a great result for some wicked sounding speakers. Thankyou again.
Great project; This week bought a pair some of these for €50. And indeed , there was no bass… After opening up the case, I found a
Great project..
This could be the solution for RL60′s wich I bought a time ago. I noticed the bass was very low ..
After opening up I noticed the plates where not any mote present. (the screws were there). I suppose the previous owner removed them. Of what material are thes plates ?? Could I use some other matereal instead ?? As I look to the pictures I think there is a big oval foam, on it an oval metal (aluminium) plate, with a recangumar copper plate on it … seems to be complex to replace …. or not , Could I do it with an Alu plate on the foam ??
I own a pair of these speakers as well. My ABR looks different though. It doesn’t have a metal plate, only the outer metal piece. I haven’t found a good replacement material yet but I love the tutorial.
I recently had to fabricate both new foam and the metal pieces for a set of these speakers. While they sound fantastic now, can anyone enlighten me as to the fine points of the metal center portion of the ABR? It appears to be 2 layers? What is the total thickness? I fabricated mine from 18ga stainless, only because that’s what I had a sheet of.
I have the same speakers but my problem is that the rubber ring from the cone is disintegrated. can you give me the spec’s of this bass speakers?
Thank a lot, André
You’re a braver man than I…what a wonderful job! I echo the sentiments of one above who takes delight in folks like you that want to preserve the B&O beauties that company has graced the world with rather than trashing for ‘newer’ which I’ve yet to see nicer (from a design perspective). I got my first set of B&O in 1978, and still have it, as well as recently augmenting, which is why I found your site. I’ve recently purchased a set of RL 140′s and RL 60.2 (thank God they’re the “.2′s” !) and am searching for either wall or floor brackets for the 60.2′s. I also need to re-fabric the grills and replace the ‘vanished’ straps on the 60′s…is that going to be a “major production” for someone who isn’t ‘mechanically gifted’? Thanks-
Just want to say hi to all you great guys, here from the land of B&O.
Maybe you will eat your heart out when I tell you, that I just bought a pair of RL 60 in perfect condition. I also had a Beomaster 3300, but it need repair. I payed the huge amount of US$30
I use RL 60 on my 1965 Beomaster 900 and Beogram 1000.
Of course we have a lot of B&O equipment here, but people start to open their eyes for the value of nostalgic gear.
Happy B&O-ing.
Karl Erik.
Hi all, nice straight forward solution. I cracked open a pair and someone had removed the abr plates completely just the plate not the surround or the rotten foam!). Any of you guys have a suggestion for replicating it or should I just fit passive radiators? Greeting from old London town by the way:)
Hi Dan,
Perhaps try to make a center plate out of thin plywood, possibly perspex or plastic.
Hi all, nice straight forward solution.Does weight and tension of foam effect frequency at which plate resonates?
0:0″ I cracked open a pair and someone had removed the abr plates completely just the plate not the surround or the rotten foam!). Any of you guys have a suggestion for replicating it or should I just fit passive radiators? Greetings from old London town by the way:)
Apologies for double entry. It’s the joy of using an iPhone on the London underground ! Additional question about weight and tension is still valid though. How do you male sure it’s resonating at a lower frequency to the active woofer to extend your range? Thanks for the response Frank
Does anyone know if rl140 had an abr or was it ported? Dont want to crack them open for no reason. Don’t think mine have ever been opened , absolutely mint. Suspect foam is starting to go on active cones though
Recently replaced the worn out foam rings by rubber rings for the bass speakers. A dedicated RL140 replacement, that last longer.
In Dutch but not that hard to understand; look for RL140 at http://www.speakerrepairshop.nl
I can confirm that the RL140′s do have a bass port, not an abr.
Thanx for the info. I’m working on a pair of RL 60′s right now. Some jerk used masking tape. Unbelievable! I bought these speakers at a apartment sale in Oakland by the lake also. I will try to use Felt from Michaels Art supply. Wish me luck.