some 18" woofers are suitable for Karlson couplers - I used a low qes low mass Eminence in a cabinet made from one 4'x8' sheet of plywood with good result. Cetec-Gauss marketed a 10 cubic foot 5181 K18 and I've posted those plans many times
a Karlson slotted tube waveguide wouldhave better vertical coverage than most horn
http://db.audioasylum.com/cgi/m.mpl?forum=hug&n=112737
1-sheet coupler
a slotted HF waveguide might mounted inside per Karlson's 1965 "x15"
a Karlson slotted tube waveguide wouldhave better vertical coverage than most horn
http://db.audioasylum.com/cgi/m.mpl?forum=hug&n=112737
1-sheet coupler
An externally hosted image should be here but it was not working when we last tested it.
a slotted HF waveguide might mounted inside per Karlson's 1965 "x15"
An externally hosted image should be here but it was not working when we last tested it.
