Moved from medium attic like room to larger room, everything is too bright

@rwbadley okay I turned up the crossover point on the subs (also mentioned by @erik_squires), moved the speakers closer to the wall (they were over a meter away) and positioned the subs as recommended. Difference is night and day. Actually quite happy now. 
just a word on the KLH model 5s … they actually sound as good to me overall as much more expensive speakers that I previously auditioned. In this case, their placement was wrong. 
thanks again. 
 

@atanarjuat99 

The KLH 5 has a couple of nasty resonances slightly below and above 20kHz. Also a rock&roll bottom with a quick fade. What music genres are preferred?

See KLH Model Five loudspeaker | Stereophile.com and KLH Model Five loudspeaker Measurements | Stereophile.com

Have you tried lowering the Mid-HF to Med or Lo? Back in the day, we would tape a thin cloth or a single ply tissue over the tweeter to help tame the highs.

If possible don't have the seating close to a wall... and dampen the rear wall so it does not reflect.

The subs have no phase and only a polarity control, making integration a bit more difficult. Their output @ 30Hz is only slightly better than the 5's. Perhaps try putting the subs in the corners, mid side wall, mid front and rear. IMO, integration of the 5's and the T7/x will be difficult as neither has the required mid-range support. 

See ieLogical SubterraneanHomesickBlues for a screed on sub integration.

I'm really curious how the components were selected.

And what speaker cables?

@ieales Totally agree that the Mid HF should be set to low. Fair question about the selection of components. Let me start with: this is the first genuine stereo I have set up since grad school when I bought mission speakers and a Harman Kardon amp at a big sale. So started with total ignorance.

I read online reviews of speakers and bought the KLH model 5s without listening - before buying any other component.  I did audition the Hegel H390 at a stereo store. I had gone in with the intention of buying the H190 but the H390 was so much less lively (in a good way) and also quiet that I sprang for the latter. When I started listening, I really missed the bass that had come through better in the stereo store with the JBL 100s so added the REL subs. Which were a huge improvement. The Lumin T2 was the result of reading other posts about streamers which paired well with the Hegel. No regrets vis a vis the Hegel, subs or Lumin (the DAC is head and shoulders above that of the Hegel H390). Speaker cables as well as power and ethernet are all from audiosensibility in Toronto. 

I have put the subs in the corner now and the listening sofa is mid room (with no wall behind).

Apologies for the very long response ! I am open to speaker suggestions for this particular set up and room. Not in a hurry to upgrade but it is on my radar.

If you haven't a visit to hunecke.de | Loudspeakers Calculator would be worth a visit.

Unfortunately it doesn't allow sealed subs.

If it's too daunting, PM me with dimensions and room photos and I'd have a go there and in REW.

@ieales Thanks for the offer to plug the numbers into the loudspeaker calculator. I did it myself. Actually I was pretty close to its suggestions already - after following advice of audiogon discussion members. It suggestion for the subs was not entirely practical (re tv position) but I am close and everything is sounding way better. Thanks again.