Yesterday I went to my local Hi-end audio store to give some speakers a listen. I auditioned the Paradigm Monitor 11s and also listen (briefly) to some Klipsch RF-7s. The sales associate assisting me was, lets say, very opinionated, and said something that I had never considered or heard before. He said a rear-ported speaker will provide a more "3-D" (meaning not just left and right positioning, but also a near and far ambience) image than a front ported. He illustrated this when I was listening to an orchestra with chorus piece when he switched from the front-ported Monitor 11s to the rear ported RF-7s. The spaciouness of the RF-7s did seemed more three dimensional. I had always thought that the port was the tuning/breathing apparatus for the woofers, not the tweeter-which is the primary contributer to the "airness" or "spaciousness" to a speakers sound. Is this correct? Does anyone know about advantages/disadvantages with front and rear ported mains?