Speaker choice

Hello OP,

All the above suggestions are great. IMO, if you like the sound of Harbeth speakers, you might just want to stay with their bigger models (house sound) rather than moving to other brands. Just get a bigger model but used to keep cost down

But if you wish to move into other brands, highly suggest that you audition it first. Based on what you wrote, the size of the listening area is similar to what I have, (13 x 23 for me). Although I listen near field, I still believe that stand mounts can perform well. My speakers are Ls3/5a and ATC and they can perform well (loud enough) in my listening area (80 to 90 db.). For me, the perception of the big "you are there" sound is driven by Subwoofers, that your Harbeth needed. In my case, I use 2x Rel T/7x Subs, integrated (using ROON) well in my LS3/5a. AND, I Use a good amount of Room Treatment. All this creates a Synergy that makes my small speakers sound loud enough, as long as you listen near field.

If you wish to move to other brands, I have heard the MoFi Sourcepoints which sounds great and i believe as others have said above, the Tekton models ( i have not heard them)

@starystarynite  But I couldn’t feel the speaker is not enough as the space is too huge for it. Now I have sold my speakers...

 

Not enough of what?  

In my experience for the cost of two mid-priced off shore made 'Sub-Bass' speakers a distributed bass array Swarm would have loaded your unusual room with a clearly better integrated mid to low frequency presentation, adjustable to the speakers you just sold or any future speaker choice.   

Mobile Fidelity Sourcepoint 8. Andrew Jones design.  Under 3K new with stands. Buy from Crutchfield and try them. If you don’t like, return and get full refund. Nothing to lose. If you want to spend more money and want bigger sound, try the Model 10.  4K including stands.  May not need sub. Could do alot worse for the dollar.

@starystarynite 

Check out Spendor A7.  Spendor delivers the dynamics of horn speakers with the refinement of box speakers and a huge, well defined sound stage.  Like listening to a fireworks display or kaleidescope.  Very enjoyable speakers.  

Here you go, just posted this a couple of weeks ago

Revival Atalante 3 $3,400 with stands or Revival 5 $5,100, Buchardt Audio E50 $4,500, Arendal 1528 Bookshelf 8 Bookshelf $4,500, Fritz Audio Carbon 7s $2,950 or Rev 7s $3,800, Alta Audio Alyssa $5,000, Monitor Audio Gold 200 $4,800, Dynaudio Focus 30 on sale $5,900, Perlisten R5t $4,300, Sonus Faber Sonetto III G2 $4,400, MoFi Sourcepoint 888 $5,000, ProAc DB1 $4,600 or D2 $5,000