My Cornwall serial number dates to the last month in 1985 and inside are K-33-E drivers with a K-57-R midrange and a K-77 tweeter with a B3 crossover network. They were painted professional black (that crappy nighclub black) but labelled CBB which is Cornwall Black Birch but upon sanding off the crappy black finish I found book matched Walnut wood veneers! The speakers are now my cherished speakers and are finished in beautiful Teak oiled walnut with a custom made black bamboo base/riser.