Hmm other brands managed port resonance in small speakers like Kef ? In some models , with some special design of the port tube ?
But kef also tries to second guess your room gain and also have that bass slope, meh .
I’ve personally never experienced overwhelming bass in room with speakers in my home , the closest I get is in our very tiny HT room off less than ten square meters , the cheap band pass sub is a tad booming on music it’s ok on movies.
It’s actually Canton
one of their wall mounted 5 identical smal speakers and band pass sub combinations, they have several of those packages .
I’ve had my share of bad bass , but rarely to much , so I don’t really get these bass slopes that both kef and Canton and others are doing .
I’ve lived in at least 14 different rented and self owned apartments many with concrete and brick walls in Europe.
So for me personally this adaptation of the bass to try to second guess room interaction has never worked for me.
So I think it’s a fools errand to even try . Build linear speaker let us figure it out with bass management.