Whats wrong with my system

[David A]

…
In regards to room placement.

The speakers are on the 4.8 meter wall.
The 75cm is to the rear of the speakers and the speakers are 2.10 meters apart.
They are 1.3 from the side walls... no toe in at all as recommended by Dali.

The walls are rendered and painted brick.
The floor is wooden boards on concrete with a large rug filling the space between speakers and listening position.

The listening position is mainly because in reading several documents on speakers vs listening position it seems a consensus that one third from the speaker wall brings the best balance.

On Monday and Tuesday i may have a little time to mess about with this which i haven't done for some time.

Sam at 100% is because with it turned down things get worse. It isn't about trying to maximize bass response.
The Dalis don't need help in that regard.

Comments:

1- rendered brick walls are highly reflective of both high and low frequencies which could easily lead to the hardness in sound to which you refer. I suspect your room is going to need acoustic treatment in order to achieve better sound and that you're going to need a combination of bass traps in the corners and broad range absorption at the first reflection points for each speaker on at least the wall behind the speakers and the side walls, and possibly also on the wall behind you.. In a room with the hard, reflective surfaces of your room I would recommend absorption rather than diffusion.

2- I think you may be misreading some of the things you've read about where to put the listening position. You've said that the rear of the speakers are 75 cm from the rear wall and that the listening position is 3 metres in front of the speakers. That puts the listening position 3.75 metres away from the rear wall, not 2.67 metres as it would be if it was a third of the room length from the rear wall, and that would move your listening position almost a metre closer to the speakers. I've seen some people call the wall behind the speakers the "rear wall" as you have and others call that wall the "front wall" because it's the wall in front of the listener. I suspect the things you've seen suggesting that the listening position should be one third of the room distance from the "rear wall" were referring to the wall behind the listener because if those sources were referring to the wall in front of the listener the listening position would almost always be far too close to the speakers.

3- At 100% SAM is doing 2 things, it is correcting phase response below 150 Hz and it is increasing bass extension which means it is boosting low bass. You get the phase correction just by turning SAM on at 0%, turning the SAM level up increases bass extensio0n which you say the Dalis don't need.

What that suggests to me is that your room has some pretty severe bass issues because of the brick walls and that you're sitting in a part of the room where there is a severe null, a drop in bass response, at a low frequency and boosting the SAM level to 100% is compensating for that null. I would suggest that you need bass traps in your room to help tame the room's bass response and that you need to experiment with your listening position in order to find a position where you don't have the problem with bass that you have in the current position. In order to do that you're going to have to turn SAM down to 0% and find the best listening position, the position that needs the least correction from SAM, and then start turning the SAM level up again in order to find a SAM setting that you like.