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B110 (SP1209) Buzzing.....may need a replacement or repair?

K

KC Cantiaci

pfm Member
I have a pair of Kef R107's that have what seems to be the very rare 4 ohm version of the B110 drivers (SP1209). One of them is buzzing and I've tried rotating the speaker 180 degrees in its housing but the buzzing has returned and seems to be a feature now irrespective of what way up the driver is positioned. I've tried it at all 90 degree options and sometimes, it seems ok for about a minute before the dreaded buzzing/distortion returns.

Does anyone have a solution for this? Can the speaker be fixed? If so, can anyone recommend a repairer? I had the coils fixed on a pair of the big bass drivers but it took the repairer 6 months??

Alternatively, are there any replacements for these? I really don't understand about ohms, crossovers and whatnot so unless it's a drop in replacement, anything else will probably be beyond my understanding :rolleyes:

Any help or advice would be appreciated.
 
It appears a repair is likely to be off the table. Kef told me that repairers are unlikely to touch a small'ish driver like this. And finding a replacement B110 SP1209 is seemingly impossible as it is the 4 ohm version. However, one company suggested the Monacor SPH-135 AD (or maybe a better one from the same series) and replace the pair. But this retailer also happens to have some new but old stock Celestion B110 4 ohm drivers that they have acquired. So my choice is old, but new/unused, Celestion drivers or new/modern Monacor SPH135's...... probably the Kevlar version?? Anyone have a view on this?
 
There are very few simarities between that and the B110 , especially the shape. It won't be plug and play without reworking the baffle and the crossover. Ask falcoln if they can help. They produce new B110 drivers, maybe they can get their tooling guys to rewind yours.
 
I've fit the Monacors to some 'briks, and they're a bit of a fiddle. The hole needs to be enlarged. (I built a special tool to do this.) And the recess for the frame is a little different from the KEF, so you need to be handy with a router or chisel. If you're running active, you won't have to redo the Xover as well.

I have a B110 that shares the buzzing problem. What's this rewinding repair?
 
Radfordman said:
Just a thought, an 8 Ohm B110 and a matching transformer.
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It likely will convert to 8 Ohm but unlikely that the acoustic profile with frequency would be the same as a standard 4 Ohm unit so leaving both speakers un-matched.

There's also the question of fault diagnosis. Is it worn/damaged suspension or is it a rubbing voice coil due to voice coil damage itself? If a voice coil has been buzzing it will be damaged but to what extent can only be guessed at by measurement unless the cone is removed to examine it properly.

Personally, I'd be tempted to simply replace the pair with brand new production B110 units and have the crossovers modified accordingly unless an original replacement can be found.
 
If you can't get it repaired, try this trick. Push the cone in gently with pressure on one point at the edge of the cone. Move all around and see if it is worse at one point. If it is, keep pressing it in and out, preferably with the speaker face down. If you are lucky, there may be some corrosion or lacquer that you can rub away, and the residue will fall out. I have a 10" SEAS driver that buzzed at high volume, and this cured it.
As I said, if you can't get it repaired. And are very lucky.
 
I've made a decision based on advice from Wilmslow Audio and gone for a pair of new, but original stock, Celestion versions of the B110 that are 4 ohm and an exact fit. The problem with the Monacors, as I understand, is that they aren't exactly the same size as the B110's so cabinets need some fettling to make them fit and the problem with the Kef's is the the mid range and tweeters are housed in a plastic pod and I can't bring myself to 'ruin' the casings......at least not just yet.

They should arrive tomorrow with any luck and then I'll see what's what. If they're no good, I can always look for alternative solution(s) but as Wilmslow had these in stock, they're the right physical size and 4 ohm versions, it seemed to make sense to try them first.
 
KC Cantiaci said:
It appears a repair is likely to be off the table. Kef told me that repairers are unlikely to touch a small'ish driver like this.
Click to expand...
KC Cantiaci said:
That, I'm afraid, is utter bollox.

There's nothing peculiar about the B110 and size is not an issue.

As long as the cone is intact it can be repaired.

There are a number of things that can cause a buzz, coil rubbing being the most likely.
Click to expand...
 
I can't see why transformers are not a reasonable idea to convert an 8 Ohm B110 for 4 Ohm use. It would be best to do both speakers. A transformer is used in my Rogers BBC LS3/6 and it is one of the best speakers that I own.

The transformer would not have to be very large due to the low power required by the mid unit and the restricted frequency response. Sowter may be able to supply a suitable transformer. I have no idea of the cost.

As for Celestion B110s, did not know that they existed, any details available please?
 
RustyB said:
That, I'm afraid, is utter bollox.

There's nothing peculiar about the B110 and size is not an issue.

As long as the cone is intact it can be repaired.

There are a number of things that can cause a buzz, coil rubbing being the most likely.
Click to expand...

It's what Kef told me. So I spoke to Wembley Loudspeakers and they say they can't do it. I've got one more place to try and after that, I'm out of options to retain the existing units.
 
Radfordman said:
As for Celestion B110s, did not know that they existed, any details available please?
Click to expand...

What turned up is a pair of Celestion K5C-30's. They are an exact fit as regards the dimensions and they are 4 ohm, but whether they're a match sound wise....??? They were £36 each so worth a punt as the likelihood of getting the originals repaired is diminishing :(
 
Are they Bextreene cones?

Sowter can do a suitable autotransformer for £66.37 plus VAT and postage. makes the Wharfedale transformers look like good value.
 
awkwardbydesign said:
Have you tried the pressing one side and rubbing back and forth yet? It's free, you know!
Click to expand...

I did a bit of that and it would stop for a while but then restart again. I got hold of the last repairer on the very short list and he says he can do it so I'm gonna send off the duff driver and wait for it to return and use the replacement Celestion ones in the meantime. Maybe it's me but the 107's don't sound the same since I put the replacements in. The missus commented on it too so I'm glad there is a repairer out there that can do the necessary.
 
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