Cabinet resonances are very short duration and have very low amplitude, they make no measurable contribution to RT60. Ported speakers have a port resonance (that's the purpose of the port).
thats theory but nobody test for case resonances in bass range good enough. on audio science is only show a 4 ms waterfall. this is focal alpha 65 evo
https://www.audiosciencereview.com/...cal-alpha-65-evo-review-studio-monitor.28832/ for the JBL 104 is no waterfall . there can not good compare speakers with that 4 ms waterfall.
another theory can be maybe speaker case itself do reflections in the room which make decay in bass worse. but i test on diffrent distance and room positions, the speakers always have resonance on near same FR
. I also test the focal with close port also worse resonances ~ 200 hz
I also test what happen when i measure the left focal and have a d3v which do nothing on right speaker stand. results can see here. FR near same but for example model fit at 52 hz when on both stative is focal is much worser. 6.3 . when measure focal on left stative and on right stative is d3v(play nothing), model fit is 2.7.
it is not much diffrence in t60m except at 60 hz. the d3v is btw worser in decay at 60 hz maybe because of 2 passive woofer. but the most important for mud is the 200 hz resonance. this let many music sound very worse and play a sine tone at this frequency on focal also sound very worse and mud and diffuse(can not locate where it comes). with my small speakers no problem
you can tell what you think, i am open to criticism if i measure wrong and what i should measure more ?. should i measure all speakers from back or side in nearfield to see if there diffrences in room interaction between speakers ?
I have upload the measures too. when i replace the focal with the d3v on right stand, i do nothing change on stative speaker or room position. other measures i do that are delay more than 20 min between measure are not exact same microphone position. I have a marker on desktop for middle and put the microphone so it is on middle when i look from top and it is position where the desktop plate begin. thats 5 cm before hearing position, but i can locate the position better for better repeat quality.
this is when on left and right stative is focal alpha 65 evo and left is measure, right do nothing play
this is when measure the focal on left and the focal on right is replace with a d3v in this measure . the right speakers do nothing play. it is only to test if the case of speaker have much or less influence .