by EWBrown » Thu Apr 04, 2013 7:02 pm
There were multiple variations on the Karlson cabinet design, the original was designed for 15 inch drivers, and the "coupling" was different from this cab's slotted porting. In either case, the full range drivers tended to be "shouty" and harsh, the use of a cab-top HF horn eliminates that issue.
I've even seen some photos of a scaled-down version for 8 inch full-range drivers, but haven't actually seen or heard any of them.
FWIW, the Karlsons can be operated in the normal vertical orientation, or laid flat on the back of the enclosure, though the HF speaker(s) would have to be situated separately. Try different locations in the room, they are best when located against a wall, in either location, rather than out in the center of the room (they are not bad in this mode, just the full lower octave response could be compromised).
Stay away from the modern low-efficiency 80-something dB drivers, unless you have lots of watts to spare.
/ed B
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