Speakers or room

I would start with treating the upper and lower corners of the room. Eliminating Echo slap will provide significant reduction of artifacts.

I was in a reverberant space years ago with high ceilings and many corners. Even using the very small and thin Roomtune corner traps fixed a tremendous amount of the problem

As suggested already, curtains over the window is a no brainer since it will be aesthetic as well.
A nice Persian rug looks great and may help.

With those basics done, you can listen then decide what other areas to treat.

As mentioned, you should get the speakers away from the rear walls.

If you end up with decent results, then consider upgrading to a more appropriate speaker. No use doing so unless and until you improve the room.




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Maybe get rid of current wife. Order one dozen big fat ones on-line. Place one in each corner, 2 per side at first reflection points and the rest on the floor between you and the speakers.

Face them inwards for better dispersion or outwards for more bottom end.

Seriously, you will have no happiness in that room without treating the acoustics, no matter the speaker chosen.

@b_limo posted some useful stuff and is correct about the misinformation being given out.  Plastic pot plants will not help in any meaningful way. I have posted a few times with advice gained from study and experience which I won't repeat here because there is a lot to be said.

Get an inexpensive mic. and download a free app from Holm Impulse or REW and measure your room instead of guessing. Educating yourself in matters acoustic will reward with treatments that actually help unlike wall to wall carpet or hanging drapes everywhere. These just soak up a narrow band of high frequencies, reducing them disproportionately while the rest of the spectrum are unaffected and remain bouncing around the room with overly long decay smearing and confusing.

DIY is fun and easy and allows you to choose fabric to suit the decor and you are also able to build true broad-band  absorbers instead of the lesser ones sold commercially which need to be smaller for shipping.

What works extremely well is an overhead 'cloud'  This can be a large frame at least 150mm (6") deep filled with OC 703 and suspended at least 100mm below the ceiling. I helped a friend with such a unit which was finished with concealed strip lights and the whole thing looked classy. The addition was transformative.

Good luck.

I have the LS50 not the LS50W so my take may not be correct. My LS50’s are in my small treated (with GIK panels) room, 12x11x9 and it sounds great, but without good bass. It is easy to see why the former editor of Stereophile uses them as his reference. However, when I have heard these same speakers in a bigger room they suffered in sound. Maybe your DSP capable LS50W are facing physical limits to what they can do in your big room.

You can easily go up in speaker monitor size and fill that room of yours. Some suggestions for this, that are similar to the LS50 sound but even better are the following:

TAD ME1 ($15K)
KEF Reference 1 ($5K used and really good)
Vivid Kaya S12 (not released yet, no price given, but I would want to hear this one)

Vivid Kaya 45 (floor stander but small)
Paradigm Persona 3F (floor stander)
Magico A3 (floor stander)

I love my LS50’s and the above mentioned speakers are what I demoed and considered to replace them in my small room (of course have not heard the Vivid Kaya S12)

https://www.soundstageglobal.com/index.php/shows-events/tokyo-international-audio-show-2019-tokyo-japan/902-tias-2019-laurence-dickie-outside-and-mostly-inside-the-new-vivid-audio-kaya-s12

I decided on the Yamaha NS 5000 as my final choice. They don’t sound like the LS50 but I wanted something out of left field for my office. They need a bigger room like yours for easy placement, but I know how to make it work in my small room with a lot more work.

There are plenty of integrated amps, like the new Hegel 390 ($6k), that require only 1 box to get you streaming digital.

There are also bigger active DSP speakers like the Kii and the Dutch and Dutch that are maybe an easier turn key solution for you. These guys are similar to the LS50W but should have tons more bass.

Room. Fixed the acoustics and you’ll get so much more from your system. Have it tested to know where the nodes are and what specific frequencies need to be tamed. Absorb or diffuse? Big difference. Get that right. I hate the way most acoustic treatments look. Went to Artnovion. Best looking highly specific treatment. Lower cost “tunable” alternative is ASC traps. Sometimes available used. Good place to start

To add to my previous post, the LS50W’s have waaay more bass than the passive LS50’s.  I actually preferred the bass response of the LS50W over the passive LS50’s and Rel T9i sub.  Neither speaker has much, if any, punch.  They are smooth, detailed, image like crazy and allow you to peel back layers of music that you may not of heard before, but they will not thump you in your chest.  If you’re looking for a speaker that delivers impact and large scale dynamics, you may want to look at other speakers.
My advice would be to buy a good sub, preferably 2, if not 4 (for a swarm set-up), cross the LS50W’s over around 80hz, and set up the dsp settings to your preference.  Buy room treatments and spend some time setting up and dialing in the LS50W’s.