Beovox 1200 was made in three different versions.
Can you tell us the 4-digit type number found on the serial number label?
And are they 2-way or 3-way speakers?

Martin

Hi There,

I have had a similar issue on some old Beovox's from the same time. It maybe the capacitors on the crossover has failed due to age, would be a good idea to change these or it could be the driver itself has gone faulty you could try pressing the cone gently to see if this free's it up as it could be the voice coil has seized. If you feel its hard or resistant it means its the coil seized and maybe easier to replace that one driver. Hopefully its just the capisor's as this is a easy fix providing you are able to solder just get a like for like value normally printed as a number and uf and the voltage should be the same of as close as you can to the original value. If you see BP stamped on the cap this means Bi-polar you must order a Bi polar cap as if you put a normal one in it may kill everything or blow the cap up.

Hope that helps,

Kind Regards,

Lewis