I can't argue with what you say, but the wall behind the speaker is obviously part of the room. However if you are going to design a speaker to be used near a boundary, then it requires adjustments in design to minimize it. (..)\nOne of the huge advantages of DIY, is to be able to customize designs to the architectural considerations.\n\nSo yes, I believe it is a room effect, but still one that needs correction if the intent is to have an against wall design.\n\n\nAs you point out above (my bold \/ emphasis), you can't expect a commercial speaker to perfectly mitigate any room problems in any room. Not trying to be defensive here, it's just simply not possible. That's also not what we claim to do. We claim this design will reduce SBIR effects compared to a traditional speaker, which it will. Look at any "share your frequency response" thread on this forum or elsewhere, and as I'm sure you know you will see the 100-300hz range typically look wildly uneven and with both more and wider dips than this response.\n\nHow this looks in any given room is not only dependent on the speaker and the distance between speaker and wall, but also where the listener is situated.\n\nHere is the same speaker in a different room (still no smoothing). As you can see the 100-200hz range is still what I'd say is significantly better than what I typically see, but completely different than the room I posted earlier. This time with only one dip, but a wider and more shallow one.