Dear all, thank you for your responses!
@james633 I believe you've spotted on understanding of my confusion. I feel like I need to pay more attention to listen to the vocals now, which keeps me from enjoying the music. Perhaps, my ears are still adjusting from the forward vocals of my previous speakers. Actually, I had set the Sophias tilted forward - using two pieces of spikes on the back feet and only the first short piece on the front. I thought it helped a little but the speakers looked so weird and I thought that the Wilson engineers must have a reason to tilt the mid and tweeter backwards therefore I put the front spikes back. I have also tried a shorter seat as well as putting some pillows below to increase height - which made me question myself and my hobby =) I will keep experimenting, thanks for your response now I feel like the problem is partly due to setup and partly the difference between two speakers with different sound signatures/specifications.
@shadorne I agree, it is a huge problem which I tried to resolve with putting isolation on the back and near walls for at least helping with the side reflections. I guess the 804's having a curved body and narrower body and depth gave them a little more room to breathe and as a result they dealt less with side reflections better. Also the strong (maybe artificial) midrange helped me to ignore this problem until moving to the Sophias. Alhough I cannot permanently place speakers closer to each other because of the equipment rack partly in between, I will experiment and see if it helps. Replacing equipment racks would at least be a feasible solution, thank you.
@jafant Thank you for your input, I will definitely try moving the speakers closer and keep experimenting this weekend. It is a little harder to move the Sophias around, being 165lbs each - compared to my previous speakers less than half the weight. I guess doing some exercise is always good! I'll keep you posted.
@gpgr4blu I have tried toeing in the speakers more, but somehow it feels not it is not helping because the Wilson tweeters on axis are too hot for my taste. The paradox is, with 0 toe in, the soundstage is bigger and the center image is somehow decent - the speakers disappear more in my understanding of soundstaging. As I toe in the speakers towards my ears, then it feels like two speakers are firing from left and right which I guess curtains the center fill - although it should theoretically get stronger with the toe in process. I prefer the off-axis response but then the center fill is softer than my expectations. Also, I am used to seeing in Wilsons toed in a lot, compared to other brand therefore I should be missing something. I will keep experimenting with different angels of toe in, thank you.
@pops I have some experience with near-field monitors when I was producing music for a while in the past. Considering that Wilsons are used in some studios I will certainly try and experiment with a nearfield listening position after I move the speakers closer to each other, thank you for the thought.
I will keep you posted as I continue my experiments. Meanwhile, do you have any comments on the McIntosh SS & Wilson combo sound signature? Thank you all for your valuable input. Have a good weekend!