The Schroder limit is good in a large listening area for two channels only and most people don’t have the space to use it but it is a great tool to use. Most have 11 channels of speakers or less. The 1723 THX has three ports and to achieve the deepest bass response is closing one port and have the back of the speaker 2ft away from the wall, I did a sweep and ran REW to get a flat bass/mid response in my setup. Adding more distance from the wall will increase midrange efficiency but you will loose low end bass response if you don’t have subwoofers.