The midrange horn is a JBL 2440 with OEM 2441 diaphragm installed, the horn is a 2311, and the diffuser (lens) is a Japanese knock off of the 2308. The treble is handled by a 1950s vintage 075 annular ring horn tweeter. (AKA bullets) Both drivers have Alnico magnets. The tweeters appeared to have been in a house fire at some point when I received them, the seller denied this, but I am pretty certain that was the case (baked on soot and discoloration) - they cleaned up pretty well, and the diaphragms are the originals which is good, because the later ones do not sound as good IMHO. The XO is a 3 way 2nd order LR type that I designed and built myself some years ago.