Horns huh, have you talked to Jim Smith of Avantgarde? He will strongly beg that you put wood over the concrete. I talked to him in mid construction of my room and he talked me into the same basic construction as Dave described. I can't say if it's better since it's a tough one to A/B, but my horns sound pretty darn good in there. Call Jim, he's really helpful and would be able to really describe why it is so important.