M100 bass driver

12 replies

Recently, I had the two mid bass drivers refoamed on my Beovox M100s. One came back with both copper wires attached to the cone broken. Luckily I was able to save this one by carefully soldering the wire ends together. However, the other driver (though it looks fine on the outside) makes a buzzing noise when driven at louder volume levels or when there is lots of bass. My ear needs to close to the driver to hear it. I'm not sure exactly what is causing the buzzing, but I'm wondering if it is alright to play the speaker normally with this defect or do I need to have it repaired or find a new driver to replace it with. If I need a new driver, is it possible to find an exact replacement?

Thanks,

Aaron

Your Local dealer can provide a replacement cone for you as they are still available to order. Are you UK based? If so i can give you a rough estimate.

 

*ignore the uk based bit I can see that you live in the US.....it's early so missed that first time around :-)

Are you stating that they still produce the exact same driver available to purchase?

ducha wrote:

Are you stating that they still produce the exact same driver available to purchase?

I'm happy to stand corrected, but I'd be shocked if this is the case. You might be able to find a suitable 'new' alternative as I did for the 8inch woofer in my MC120.2s, but B&O are not know for their far reaching support for 1970s products!

 

j0hnbarker wrote:
I'm happy to stand corrected, but I'd be shocked if this is the case.

DITTO!

................hands up, I got confuddled between the Beovox M100s and cx100 which you can still order parts for.

BeoChime wrote:

................hands up, I got confuddled between the Beovox M100s and cx100 which you can still order parts for.

No worries - and you're quite right about CX50/100 drivers too :)

 

As for the buzzing, is there anything at all loose inside the cabinet which could be causing this? There is also the chance that the drive coil hasn't been centred correctly when refoamed but I would also expect to hear distortion even at lower volumes if this was the case.

I know it is extra work but you should try swapping the drivers over and see if the problem follows this speaker or if it exists in the cabinet somewhere........ Actually on this basis it would also be worth simply switching the cables on the amp output first and see if the problem switches speakers to rule out the amplifier.

Chris.

I agree with Chris on the centering - an important step that many pro refoam'ers skip (?!) - and the
swapping.

If that's the "Filler" driver, then the same driver is found in Beovox M75, if thats of any help.

- And one more thing; Find a new refoam'er.

Martin

Listening to the buzzing, it really sounds as though it is coming from the driver itself. I made sure that there were no wires or anything near the driver that could cause vibration within the cabinet when I reinstalled the unit back in place. I was initially thinking myself that the drive coil wasn't exactly centered. I have read that this can be harder to do on smaller diameter speakers. My big question now though is: Am I potentially damaging the driver by continuing to play the speakers?? 

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