I have not seen a factory driver surround with the overflap tucked to the underside of the cone. Certainly not with anything B&O has put out.

Whats going on here is the S80.2 sounds fine at lower and middle volume levels but at around 4:4 or above on a BM 5000 the bass or lower harmonics become really muddy and distroted. Doesnt apper to be an issue with the voice coil rubbing as I dont get any scratch. It is worse when listening to compressed files MP3 etc as opposed to vinyl or CD.

The recap was done last summer but never really took note of the refoam job until more recently. The curve is compressed to a tighter peak point looking more triangular than having a wider more of semicircular roundover.

Not really looking forward to refoaming another set of professionally refoamed drivers but it just doesnt look or sound correect.

Or is it K to do it this way and my problems with the bass harmonics are elsewhere.

 

From a mecanics point of view, with the surround behind the cone the voicecoil is not radial centeret, with the surround to the front, the center will be some 1-2 Mm more to the back, so if your crossover is OK and your BM is OK yes i think this could cause the distortion.

MP3 files below 320 kbs are always a PIB, and even at 320 you will hear a big diff to vinyl and good CDs

The dust caplooks very big to me.

 

You are probably right and it looks to be pushed forward a bit compared to my set of S50 refoamed by me. Similar speaker and driver but not the same. Once  swaped the speakers set (currently listening to the Stones iTunes MP3 on the same BM 5000 with the S50 and the lower harmonics are much cleaner and crisper.

My first thought was problems with the iTunes/Sound Utilities MIDI so messed with that some but the strange part about it is sometimes a certain song would play fine then other times not. Really quite irritating.

I am just hoping someone comes along and tells me all is fine and I merely need to pack  in more damping foam.

My dear girl, refaoming is fun, and admit that you love it, but maybe wait a little to see what the geeks are recommending

No its not fun, It is somewhat time consuming requiring patience and a delicate touch. The touch I have the patience however is nowhere to be found. I have ony to gears fast and faster.

Slow tedious work drives me nuts. I tend to wait impatiently while the glue set up often peeking around the speaker to see if it is set up enough to continue on to the next step. Very annoying work.

I do like this, first remove old surrounds, clean, all units ready for gluing first fase, in the evening just before bedtime, glue surrounds to  cone, next day evening, take of dust cap, shim, just before bedtime, glue to frame, next day check and new dustcap, meanwhile I do crossovers and cabinets. I like it, its a piece of precition work that cannot be rushed.

Wood works, no stripper. Sanding with 200 grain and fast oscilating sander until laquer gone, sand with 400 grain and sander, dents and deaper scratches, with a folded 400 sheet, clean of laquer, ad water to dents and scratches, the wood will come up, let dry, sand lightly with hand and 400 grain, I like the natural color of the wood and I polish it with boiled linseed oil, if laquer, sand with hand and 1000 grain, laquer, sand 1000 grain, laquer.

Use marine grade laquer, it will keep its clearness where cheap ones gets yellow, more so in the sun.

Eugene:

No its not fun, It is somewhat time consuming requiring patience and a delicate touch. The touch I have the patience however is nowhere to be found. I have ony to gears fast and faster.

Slow tedious work drives me nuts. I tend to wait impatiently while the glue set up often peeking around the speaker to see if it is set up enough to continue on to the next step. Very annoying work.

 

I'm with you 100% Eugene.

I am often accused of having the patience of a gnat by SWMBO and she is probably bang on the mark. I cannot abide waiting for hours on end for glue to set on the inner cone edges before I can start with the outers.... what a waste of life that is. I NEVER use use the slow PVA type adhesives when refoaming (partly because they are rubbish - I have bought speakers which have been refoamed using these products & had to re-re-foam them!) & always opt for using faster curing products.

Chris.

Søren Mexico:

I do like this, first remove old surrounds, clean, all units ready for gluing first fase, in the evening just before bedtime, glue surrounds to  cone, next day evening, take of dust cap, shim, just before bedtime, glue to frame, next day check and new dustcap, meanwhile I do crossovers and cabinets. I like it, its a piece of precition work that cannot be rushed.

Wood works, no stripper. Sanding with 200 grain and fast oscilating sander until laquer gone, sand with 400 grain and sander, dents and deaper scratches, with a folded 400 sheet, clean of laquer, ad water to dents and scratches, the wood will come up, let dry, sand lightly with hand and 400 grain, I like the natural color of the wood and I polish it with boiled linseed oil, if laquer, sand with hand and 1000 grain, laquer, sand 1000 grain, laquer.

Use marine grade laquer, it will keep its clearness where cheap ones gets yellow, more so in the sun.

That is more or less how I have done my surrounds in the past Soren so I dont go insane. Still not my cup of tea. The prevoius set that was professionally refoamed that I had to re-refoam was a set of CX100. Three drivers were fine but one was visably out of kilter and would scratch even at low to moderate listening levels.

I was able to use my finger to shift the cone to proper center and stop the scratch but who wants to  relax and listen to music with there finger pressing on driver cone to keep it centered proper. My solution at the time was a bit of that blue painters tape affixed to the cone I then pulled the cone to center the driver and taped it to the speaker frame. It actually worked until the new surrounds arrived from Holland a few weeks later.

Not that I would ever recommend that as a temporary or god forbid, permanent solution.

I was thinking more of a satin topcoat finish, I dont really like the glossy look on stained woodwork. Bummer I have a big heavy belt sander I inherited from my step-father I was itching to use. I am sure it would peel off  everything, and I mean everything off in short order.

Medogsfat:

Eugene:

No its not fun, It is somewhat time consuming requiring patience and a delicate touch. The touch I have the patience however is nowhere to be found. I have ony to gears fast and faster.

Slow tedious work drives me nuts. I tend to wait impatiently while the glue set up often peeking around the speaker to see if it is set up enough to continue on to the next step. Very annoying work.

 

I'm with you 100% Eugene.

 

I am often accused of having the patience of a gnat by SWMBO and she is probably bang on the mark. I cannot abide waiting for hours on end for glue to set on the inner cone edges before I can start with the outers.... what a waste of life that is. I NEVER use use the slow PVA type adhesives when refoaming (partly because they are rubbish - I have bought speakers which have been refoamed using these products & had to re-re-foam them!) & always opt for using faster curing products.

Chris.

I dislike it so much I opt for rubber replacements rather than the genuine factiory foam and damned be  those who dont agree. These are MY speakers and I can do whatever I want to them.

Below is an example of my wrongheaded dodgey rubber surround replacemnt work on my S50's.

at least I didnt glue the overlap under the cone and it sounds fine. Nice and clear without mud in the lower harmonics.

Dont ever use your belt sander, use a light oscilating, the belt sander will rip everything of very fast even with a fine band.

Foam rings, try here, cheap and over here

http://shop.ebay.com/bootapest2/m.html

Are you sure that's the original S80 woofer ?
Any chance of a photo of the magnet/backside ?

Martin

Dillen:

Are you sure that's the original S80 woofer ?
Any chance of a photo of the magnet/backside ?

Martin

A real good chance Dillen

That's an original woofer alright.
Wonder why someone went through all the trouble of reverse mounting the surround.
I agree, that can easily give distortion.

Martin

Dillen:

That's an original woofer alright.
Wonder why someone went through all the trouble of reverse mounting the surround.
I agree, that can easily give distortion.

Martin

......  I was hoping you would say, "its alright Eugene just stuff it full of damping foam".

As Søren suggested earlier, fitting the surround behind the cone like this
introduces a certain pre-tension on the cones axial movement.
In other words, it will initially move easier one way than the other.
That is bound to give distortion.
There could be another fault but I would correct this before eventually diagnosing further. 

It's much more difficult to reverse mount the surround like this than to do it the
traditional way. Cleaning it off again could also prove a bit difficult.

Martin

Maybe it will help if you turn the speaker facing against the wall, then it would play kind of backward and compensate for the bad surround, then you could mount the fret to the back and you'r done

Come on girl, refoam, and tell os how it went.

As a surprise for my father, I refoamed an old pair of his speakers for him. The foam lip was originally glued to the underside of the cone, so that's what I did. One speaker turned out great. The other scratches and so forth low/midway on the volume scale.

Martin, do you remember? We talked about it for a couple days. Could this contribute to my problem?

To me, glueing the foam ring to the underside is commonplace. Recalling all of my speakers, I can not think of any of the top of my head that are mounted differently. I may be forgetting some though.

Did you shim up the coil/center piece ? And if you did, was it difficult to get it right ?
The spider ?
Did the woofer play for a long time with the bad surround ?

Martin

Shimming was no problem and from what I could tell the spider was fine.

The unit was used extensively with the damaged ring.

Eugene:

 My solution at the time was a bit of that blue painters tape affixed to the cone I then pulled the cone to center the driver and taped it to the speaker frame. It actually worked until the new surrounds arrived from Holland a few weeks later.

 

seen a similar repair done to two pairs of M75's I bought a few years ago. They had used brown parcel tape though. You could tell it had been there for few years too. They were aligned though as the coils were fine. Some new rings, and they were perfect.

 

Craig

Hi Eugene,

About the woodwork: what Soren says probably works good but what usually is advised here is Danish Oil: it will give a finish just like the original on the loudspeakers wood. Some like to use beeswax. There are some threads around on wood restoration, give it a search!

Good luck with the refoam!

I have a sneaky feeling that Eugene (like myself) would like to finish the cabinets & have done with them, never having to touch them again other than general cleaning/polishing. Danish oil is indeed very good & gives a wonderful finish but needs revisiting annually. That's why I always French polish my cabinets - fairly work intensive to get the desired finish but it will last a lifetime when you achieve it.

Chris. 

Medogsfat:

I have a sneaky feeling that Eugene (like myself) would like to finish the cabinets & have done with them, never having to touch them again other than general cleaning/polishing. Danish oil is indeed very good & gives a wonderful finish but needs revisiting annually. That's why I always French polish my cabinets - fairly work intensive to get the desired finish but it will last a lifetime when you achieve it.

Chris. 

and you are right Chris most likely the will be top coated with a satin poly urethane based finsih. I could clean ir with a wash cloth from then on.

The satin polyU. is a nice finish and will last for years, Linseed or Danish oil needs a treatment once a year. Boiled Liseed oil gives the same result as Danish oil, which is mainly Linseed oil with some additives to make it harder, but boiled Linseed oil is, like French polish, an old and traditional way to tread and protect wood.

I use marine grade satin polyU. on my newly installed doors in my house, Eugene wrote in the thread that she only laquer one time. What happens when you strip or grind of old laquer is that you comes down to raw wood, when laquering the first time the broken fibers of the wood will raise, striking the surface with your finger tips and you will feel a like sandpaper surface, after the first layer sand lightly until you have a smooooth surface and laquer again, the surface after the first layer is now hard and sealed and after sanding and second layer will stay smooth. Applying the second layer its important to work in a dust free environment, I do it in my garage, before applying it, I water my floor and wait one hour before applying, that binds the the dust. To get all dust of the surfaces I use lint free rags slightly humid, used after brushing clean the surface.

I dont like this kind of work so for me French polish is Polish for me