what is the best way to deal w/ an asymnetrical ..

TacT RCS 2.0 or 2.2. Best room correction I've heard, and one seems to be up for grabs here (no affiliation).

Seems like you'd want to have some absorption sound panels, or perhaps simply enough absorptive objects, along the solid wall opposite the opening to balance out the two sides. The imbalance would be that you are getting no reflections from the open side, while getting a direct reflection from the wall opposite. Rives would be a good resource to answer this question.

Marco

I have a similar problem in my listening room. What I would suggest you do first is: THE PLACEMENT!!!
CARA software is very good, if you really want to approach it in scientific way.
Then, I would second Maggieq advice on TacT RCS 2.0 (or if you also want an updated DAC AND ADC 2.0s, OR 2.2X).
I just bought TacT myself, and let me tell you: the difference is not insignificant. I don't know if you can possibly reproduce it, using anything else, other than a room correction device.
And, of course, room acoustic treatments. Good luck.

I have a friend whose room is a virtual cube (about as tall as it is wide and long, completely open on one side. The room is very problematic. About the only realistic thing that can be done is to listen in the nearfield, where room contribution is relatively insignificant. This requires finding speakers that sound good fairly up close to the listener (find speakers that are not too brigth). Some Spendor speakers, the JM Reynard line, for example, come to mind.

I am not sure that an asymmetrical room is any problem. In a concert hall, most of the audience sits towards one sidewall or the other. My room is very asymmetrical, straight wall with windows and fireplace on one side, and multiple hallways and a staircase on the other. Also, the walls have lots of irregular jogs, and there are several alcoves. Furniture goes where it is useful and looks good, and that's not symmetrical. Bottom line is that standing waves have a hard time getting established.

When designing loudspeaker enclosures, an asymmetrical box and offset driver locations is considered a good idea. Why not for the big box we call our "listening room"?