Most likely a stuck coil caused by a lose magnet. It happens in transport and when moving
the speakers around and is a matter of old glue letting go.
The two woofers (all four) are identical and should also feel so.

The same applies to the slightly more common Beovox P45.

Martin

OK, that sounds bad. So, am I looking for a pair of P50 woofers? What are my options?

P.S. I've been through this before with a pair of dead S45s. I have no regrets.

Beovox P45 and P50 woofers are identical.
Not that it helps a lot, I'm afraid.

These are wonderful speakers and I am still experimenting with finding a fix for the woofers.
They are not easy to match with any modern replacements, at least none I've found so far
so the best would be to repair the originals if possible.
So hang on to them, I'm sure that a solution will suddenly come up.

Martin

I expect you know these speakers better than anyone, Martin, but I did get a reply on 'another forum' that I'd like you react to:

"You should pull it too see if it is a passive radiator or a woofer. It is possible that one woofer reproduces the sub harmonics and the other the upper mid band freqencies which would cause one woofer to be much stiffer then the other."

I've seen more than a few.

The filters sort different frequencies to them, one acting as a filler and the other as woofer but the two
drivers are perfectly identical, with same part no's so they should look and feel the same when dismounted.

There are no passive elements in any of the P-series speakers.

Martin