This
from the SUNN Shack as posted by Conrad Sundholm.
In Reply to: Sunn 1960s "Folded Horn" Cab Specs??? posted by Karl on September 05, 1999 at 12:27:24:
This design came to me in the twilight of my sleep. I don not have any drawings of the cabinet, but I do have a memory of its construction. The cabinet's external dimensions are 24" wide, 36" tall and 15" deep. A 1/2" plywood liner was placed on the inside front edge of the cabinet to make it look "beefy". The port in the 2 X 15" cabinet was 5" high and ran the entire width of the cabinet. The horn baffle was formed out of two pieces of 1/2" plywood. The horizontal piece being about 3 to 3-1/2" in depth and the 45 degree angle piece being 9" long. On the dual 15" cabinet there were two baffle assemblies. The 1/2" plywood horn baffle pieces were glued into routed grooves in the sides of the cabinet. The single 15" was simply 1/2 of the dual 15" cabinet with the port at the bottom of the cabinet with a single horn baffle assembly. I could sketch it for you but no draw capabilities on this e-mail response mechanism. I would be more than happy to send you a sketch.
These were loaded with JBL 140's but you could use the same basic design and adjust cab sizes to match whatever speaker you want to use.
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