I recently got a pair of RL6000's, which although in fine technical condition, were dirty. So here's a short "workshop" on the cleaning process, hopefully useful to someone else as well. Sorry for the highly un-Beoliving environment - things move so fast at the office that it is a constant mess

Unfortunately I didn't take a good "before" picture, so here's the worse one after I did everything I could to clean it dry. In addition to the "dust ghosts" on the driver cutouts that make any speaker look bad, this one seemed to have sucked some dirty cleaning water or something else from the floor.

So, we'll need to dismantle the speaker and see if we can really wash the fabric without ruining anything. First, the two mylar straps will have to come off if you're lucky to still have them. Each of them is held by a triangular plastic block in the rear, fixed with one screw. Loosen it and you can slide the straps off over the speaker ends. Clean them and try not to break them.

Then, you can remove the back shell of the speaker. There is one screw in the bottom of the connector bay, two more under the strap holders and six around the speaker perimeter in these models. Then you can just lift off the back shell. There is a foam gasket, so it can be pretty tight (the "line" will still stay fixed on the front baffle, pry with your fingers in the groove just above it).

Once you have the back loose, peek under it and see how the wires from the connector panel to the crossover go. They have just enough length that you can unplug them from the panel, and then lift the shell completely off. Note the positions of the damping blocks so you can put them back properly later.

(models like RL60.2 which also have a DIN connector in the corner may require disconnecting it now as well, I can't remember.)

Now you see all the innards. Make good notes of where everything goes - preferably take a good picture, which I obviously forgot - and then start removing things. Felt pen markings across the perimeter of the drivers make it easy to replace them correctly and in the same position.

Otherwise it's easy, just screws, brackets and more foam & rubber gaskets. The two drivers seem otherwise identical, but the gaskets are different, so don't mix them.

Now would be an excellent time to recap the crossover. I'm not going to do that now - but since RL6000 service manual isn't on site, here's a parts list - for this pair, anyway... Check the solderings as well - these were all fine.

• 22 uF / 63 V (which I would upgrade to 100V)
• 15 uF / 100 V
• 5.6 uF / 100 V  (two of these)
• (and a 3.3 uF / 100 V plastic cap, which probably won't need replacing)
  

Back to the actual business at hand. There's still stuff to remove - namely the actual red (or silver...) line. This model has just four screws around the perimeter and then that part of the frame lifts off. Now we have a great opportunity to clean the dust from these otherwise impossible grooves!

Then, we can see what we can do with the fabric. It is glued around the perimeter of the front baffle, under the straps, and on the "Bang & Olufsen" script so that it shows through. Apart from the glue, there should be nothing left that could be damaged by water (don't do this with the smaller models that have, I believe, a chipboard front!).

Luckily, the glue doesn't seem to mind water at all so we can splash all we want. I first tried lukewarm water, but the stains didn't come off, so I decided to try my luck with mild dishwashing liquid. It worked better, helped with a soft brush.

What makes this difficult is that at least this black cloth will look very clean as long as it remains wet, so you don't know right away whether you were successful. Also, rinse well so that the last puddle of dirty water won't leave a stain once it's evaporated.

I managed to resist the temptation to use a hair dryer in case the moisture and heat together would finally dissolve the glue. Here's the dirtier front cover while still wet.

Let the front covers dry properly - moisture trapped inside the speaker can't be a good thing - and then inspect the results.

Mine are still a tad damp, so I'll return with the assembly process and final results after I've run some errands meanwhile.

***

Back from shopping, it's been almost four hours since I first started, and motivation is slightly diminishing. Some adjustment oil is therefore necessary.

The covers are now dry, so it's back to everyone's favourite from all service manuals: "assembly is the reverse of dissassembly."

Install the "Red Line" frame, and then position the drivers and the crossover back where they were. Install all brackets and replug the wires. If any of the connectors have become loose, pinch them a little with pliers before reinserting. A high-endist would replace the wires and solder them on without connectors, but I can't be bothered. Also, squeeze the wires back between the plastic pin holders so they won't have a chance of rattling about at high volume.

Here's one I prepared earlier (don't you love that one as well?):

Position the damping blocks where they were and reinstall the back cover. Make sure the foam gasket slides in as it was and doesn't get crumbled. Tighten the screws, going from one position to the opposite like you were reinstalling a cylinder head. This will make you feel good.

Oh yes, don't forget to reconnect the input wires to the connector panel before tightening everything

Now, there are only the straps left. Wrap them back on - on RL6000's they have no markings so the position doesn't matter - and tighten carefully after making sure they are located in the groove all around. You definitely do not want to snap them now!

And after assembling the second speaker, here is the end result! The dirtier one (on the right here) still isn't perfect - I believe what ever had splashed on it was strong enough to actually discolour the fabric - but they are immensely better than when I started. These shiny black speakers would be a perfect fit to the BC8000 in the background in a less busy environment I have yet to decide where they end up...

And that concludes the afternoon in my workshop. I hope the readership finds this useful or at least entertaining.

Thanks Mika, we love these threads on here!
I have some Redlines that I haven't looked at yet, so you have given me the impetus needed.

Cheers mate!

Thank Mika, great thread. Looks like all Redlines are pretty much the same inside.

Craig

that is great Mika, it has given me the confidence to give my RL 60.2 speakers a proper overhaul, they must be over 20 years old, and due a re-vamp.

Good luck, it is quite rewarding! I actually recapped a pair of 60.2s as well this winter, but that thread is pretty much useless since the pictures didn't survive the forum upgrade.

Anyway, the thing I learned was not to trust the service manual, the crossovers in mine were quite different in the tweeter network. So open them up first and check the values before ordering new caps.

The end result was well worth it. They sound so different that it actually took a while just to get accustomed to the change.

good to know,  I am sure that if you sent the pictures to Keith or Lee again, they could re-instate them for us

Recapping both set of my Redlines the 60.2 and the 60's made all the difference in the world. Wasnt really all that difficult. But Mika is correct in stating check your board. The cross on his set looks nothing like the cross on mine.  As I recall my caps were 22uf 15 uf and two 6.8 uf for the 60.2 and 15, 10, 6.8 and 4.8 uf for the 60's. and then there are the resistor values which can be different. 

I went ahead a reclothed mine while I was at it.

tournedos:

<snip>

I hope the readership finds this useful or at least entertaining.

I found it both!  In my opinion these write-ups are one of the essential ingredients of BeoWorld, and I hope that posts like yours will encourage more people to create more - Great work.

Eugene1960:

Recapping both set of my Redlines the 60.2 and the 60's made all the difference in the world. Wasnt really all that difficult. But Mika is correct in stating check your board. The cross on his set looks nothing like the cross on mine.  As I recall my caps were 22uf 15 uf and two 6.8 uf for the 60.2 and 15, 10, 6.8 and 4.8 uf for the 60's. and then there are the resistor values which can be different. 

I went ahead a reclothed mine while I was at it.

That's an excellent idea - for some reason I'd not thought about "colour changing"  RL's..  is there any chance of more/bigger pics?

tournedos:

 Tighten the screws, going from one position to the opposite like you were reinstalling a cylinder head. This will make you feel good.

Love it, Mika!

Sure Ray no problem.

I like those, Eugene! Would look great in a suitable environment.

ouverture:

good to know,  I am sure that if you sent the pictures to Keith or Lee again, they could re-instate them for us

Actually they are not that relevant - mine were apparently a very early pair, and the crossovers were constructed on chipboard. You're more likely to have real printed circuit boards, and the job will be much easier.

Anyway, here's the schematic from another thread - the left version is from the service manual, the right is what I had in my 60.2's. The bass & mid networks were identical with the manual version.

tournedos:

I like those, Eugene! Would look great in a suitable environment.

I agree.  Very nice indeed.  Thanks for the pics!