cristipatrick
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B&O rattle problem ?
shp
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It sounds like you've blown the woofer. Normally if you push on the paper of the cone, it should go in and out silently.

But it sounds like your woofer is making the rubbing sounds. So the voice coil is damaged. At moderate volume, there's a little bit of rubbing. At higher volume, more rubbing. And maybe if you press it a certain way you offset the "bend" in the voice coil enough so the rubbing sounds quiter; push somewhere else on the cone and you make it worse.

A new woofer should fix the problem. But if you have a local B&O dealer - or really any quality hi-fi shop -- they should be able to confirm and will probably be willing to repair it for you.

Scott

commsysman
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cristipatrick wrote:

Hi everyone,
I have a small issue with a pair of speakers. A rattle (I think in english) with the woofer. The speakers are B&O Beovox3000(1970-1980) and Marantz PM57 amplifier. The speakers sound good, but at a mid-high volume, the woofer has a rattle... the cone and dust cone are made from paper, the surround is from some kinda of textile that looks pretty strong. I am not sure if they were ever repaired or something. Another thing is that the rattle seems to come only from a part of the speaker. If I touch the surround while is playing it intensify even more, to the point of really crunchy(?) sound. Also when nothing is playing if you press gently on the cone there is a sound like you would rub two pieces of paper, but nothing is touching, this happens with the speaker in the cabinet and with it outside. If you touch the speaker at 180 degrees , again: while is playing it has no effect(no intensification), and with no sound the "rubbing paper" sound does not happen. I looked inside, they seem in good condition. I saw some things on the internet. I looked inside, under the surrounding textile, and there where some big pieces of glue, you could feel them from the front as well. I have detached them, but still... also the other speaker has some big pieces of glue on the inside, but rattle does not happen, until I think if I push it to high volumes... Thank you. Also, I was thinking to put some new 10" woofers with rubber surround. Thank you, looking forward to see your suggestions.

The "rubbing paper" sound is the voice coil assembly rubbing against the magnet assembly. This is due to distortion of the cone. It is not repairable.

The only way to repair this is to buy new replacement drivers from the original manufacturer.

The kind of "mickey-mouse" repairs you are attempting is like trying to repair a racing engine with some old VW parts; it's not going to work.

cristipatrick
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Thank you for the answers, although it can get to a decent volume without perceptible distortion, the other one can go much louder. I think would be a smaller pain if I just replace them with a new 10" woofers... should I just go for some speakers that are 4Ohm as it is specified on them ? Would you recommend something you maybe tried, like a model or a brand ?

shp
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Cristipatrick

The speakers are quite old. If you want to repair them, contact a B&O dealer. You can find your local dealer at this link http://www.bang-olufsen.com/en/store-locator Don't just put any 10" woofer into the speaker - get the right driver if you can. Otherwise your two speakers will sound different, you run the risk that you might damage the crossover and you might find the driver won't mount correctly.

If B&O doesn't have any parts, you can try eBay for used Beovox 3000 that you can use for parts.

If you're asking about buying new speakers, it really depends on your budget. I would start with Stereophile's recommended components list. You can also consider used (but newer than your Beovox) speakers on Audiogon, eBay, etc. Brands that are generally good new or used and have been around a while include B&W, PSB, KEF, Dynaudio, Wharfdale, Tannoy, Vandersteen, and Focal.

cristipatrick
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Thank you shp, I was thinking of changing both of them as it would have balanced sound, but am not sure about different specification that need to be checked, you said something about the filters... Not yet looked after some original replacements.

geoffkait
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Run, don't walk, to your nearest Walmart and buy the Pioneer Speakers they sell for $79. They will kill the B&Os. You can donate the B&Os to Goodwill. These particular speakers are from the same dude Andrew Jones that makes the Pioneer Reference One $37K speakers. Also available on Amazon. It's gold, Jerry, gold!!

Geoff Kait
Machina Dynamica

wkhanna
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As I believe the OP is not from our continent, he may not have the same access to the Pioneer speakers you reference.
But good advise, regardless.

Unless the Thiele/Small Parameters of the original drivers are known, it would not be possible to replace them unless you could locate original drivers in good condition (& take measurements on them for everyone else).

It is highly unlikely that simply replacing the driver with one that fits the same opening in the cabinet will have many of the same characteristics as the original.

As was mentioned earlier, the crossover components were chosen specifically for the drivers in the original design.
Putting different drivers in would produce a frequency response that was not flat (desired) either within the crossover range or outside of it.

Even if you could get the same or very similar drivers, these speakers would remain little more than a novelty, in my humble opinion.

Bill - on the Hill
Practicing Curmudgeon & Audio Snob
- just an “ON” switch, Please –

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