Bang & Olufsen Redline 60 speaker repair plate

I bought a set of Bang & Olufsen Redline 60 speakers (The earlier 6503 model). They had a very common problem where the bass radiator plate had foam rotted into oblivion and rattled around inside the speaker instead of radiating anything. B&O knew it was a problem and in the next revision of the speakers changed from having a radiator plate to having a more common bass reflex port. They even sold a retrofit kit for quite awhile. However these speakers are now ~35yrs old. no more parts.

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