Of course, they gain some from corner loading and room gain but still, there are issues both pro and con, mostly related to the fact that a portable basshorn is limited in size to something well under wavelength proportions. If built-in to the structure, other possibilities open up but that's a rare installation indeed. In most cass, basshorns are much smaller than wavelength scale.

This is the prosound forum, and I was really talking about prosound applications when I posted this. The goal is SPL and quality is important, but flat response isn't really on the menu. I still prefer to have distortion and compression very low and as flat response as possible, even if multiples are required. The goals are similar, but emphasis is on output. Anyway, I was really looking for strenghths and weaknesses of various folding paterns, if a basshorn is a given. I'd also like to make the assumption that horns have the same properties of length, area, expansion rate, electromechanical parameters and front and rear chambers, so that the comparison remains solely that of folding patterns themselves.

But I like the discussion of the strengths and weaknesses of basshorns in general too. I realize the limitations of them at the deepest frequencies, and don't consider them to be without fault. So I've opened a thread called "Basshorns - Pro and Con" in the High Efficiency forum. We can discuss the more general basshorn matters there.