The Delta 15A is the 8ohm version and the Delta 15B is the 16ohm version.
If your going to wire in parallel 2x8ohm =4ohm or 2x16ohm=8ohm
wire to match your output transformer, i believe the Blackface bassman only came with a single 4ohm output. You should confirm that.
Blackface Bassman aa864 schematic Delta 15B 16ohm Delta 15A 8ohm Selenium 15PWP-SLF
if you want to spend the cash for a lighter speaker than
Kappalite 3015
Otherwise to hold its collectors value hunt down a pair of JBL
D-140 or K-140 and recone. If i understand correctly there is no D-140 cones and it can be redone with a K-140 cone.
DO NOT use weber as a recone service, use original JBL parts
Non of those drivers above sound anything like the original JBL's
the JBL D-140 or later K-140 was the top of the line speaker in 1968.....otherwise it would have a Utah, Oxford or Rola speaker.
