Speakers I got on Freegle and re-built. They were Sanyo mid-price ones which had pretty much burned out. I was kindly given a pair of Bose speakers that were about 25 years old, but the cases were knackered.
So the Bose drivers were removed and transplanted into the Sanyo cases and viola...
The red things are bits of cardboard to cover holes where the original mid-range drivers were, the Bose mids are underneath in new holes I cut out. The cardboard vibrates nicely though creating some sort of baffle effect.
They sound amazing, driven off my genuine 1980s tuner-amp I got for £3 in a charity shop.
Cheap as chips.