The odd (or curious) part is that my experience was bass from Sapphires at LTA < Sapphires at home. And for DBT Audio it seems as if bass from Sapphires at LTA > X5s at home.
Maybe the Daedalus speakers were not in the room during DBT's listening session at LTA.
I have changed speaker cable and heard more bass, and I have changed DACs and definitely heard more bass. I have the Holo May KTE, which LTA now has, and it definitely provides a more audible bass and more timbre and texture in the bass than other DACs I've had. Aside from the major factor of the room, other parts of the system can play a role.
I'm still not entirely sure what "more bass" means. Louder mid-bass, more texture and timbre in bass instruments, audible lowest octave, more room shaking from lowest octave (separate from hearing timbre or texture)?
I do not doubt the impressions of the person at Spatial Audio either, but is he listening to speakers that are in their first 50 hours after assembly and prior to shipping? Or is he listening to Sapphires and X5s with more than 1000 hours on them both dialed in to the same listening room and the same source equipment/cabling?
It seems odd that with a powered woofer built into the X5s that it couldn't be setup to produce higher SPL in the lowest octaves than a passive system like the Sapphires. This leads me to wonder (speculate) whether the "more bass" being described is not in the lowest octaves handled by the powered woofer but rather in the mid-bass.
Could it be that the greater detail coming from the AMT gives the impression of less bass? In the Youtube direct comparison, the sound of the strings being plucked on the upright bass are more vivid and realistic from the X5, and that could draw attention away from the sound of the bass notes, even though the SPL of the bass notes is the same as in the Sapphires.