Do you think you need a subwoofer?

Raul,with all due respect I think you can use a bit more education,on the sub bass issue!
First of all,to flatly mention that two are automatically the way to go is just wrong!!...There are some circumstances to consider(crossover point),which I adhere to...before I make ANY changes in my system.
As to low bass,and the "need" for a sub...this is absolutely based on the "in room" performance of the main speakers.
A sub can be added for different reasons,and I will give you two...
Firstly,if the main speaker does not go "very low" in bass,then your theory is best,and one will "most likely" benefit from two subs....BTW,I have owned two BIG Infinity speaker systems,BOTH employing two multi driver sub cabinets,so I know about the bass issue in my room.
My current speakers,unlike yours are moved quite far out into my room,to maximize their amazing soundstage capabilities.I can do this because I have a dedicated room.However,one loses some bass impact(not frquency loss)due to the "particular" room loading issue.
I have useable output down to the mid to low thirty hz with this positioning,but the extreme bottom needs a bit of added heft.Not alot,and at very low frequencies!Most likely lower than you go in "your set-up"!From your pictures,you seem to have the main speaker far back,which affects stage depth.

So,the second point(one you MUST take into account before automatically telling someone to spend money on a second sub)is "how low do the main speakers go,in the room,and where does one need to crossover to a sub"?
Before I made any sub choice,I obtained the advice of Dave Wilson(I think he knows a bit about the subject),and maybe you don't know that bass frequencies below 60 hz are perceived as "omni directional",so if the "main" speakers go low enough,and one crosses over low enough(I crossover at 24 hz)then the issue of two subs comes down to a pretty irrelevant decision.
If one sub, set up with very good room loading/blend,and coming in very low,does the job,and if the main speaker has superb low bass output,the second sub is not a necessity.
Of course if one needs the sub to crossover in the upper bass,then two is the way to go.I believe your thoughts relate to a higher crossover point then I need.
I'm going with Dave Wilson on this one,not to mention that I am quite satisfied.
Best.

Dear Sirspeedy: +++++ " and maybe you don't know that bass frequencies below 60 hz are perceived as "omni directional",so .... " ++++++

certainly that I know about.

Sirspeedy till you understand what means intermodulation distortion and harmonic distortion specially on non self-powered loudspeakers ( any ) we can't follow speaking about because you are talking only about low bass response that it is only one of several aplications of subwoofers and IMHO not the most important to improve the quality sound reproduction in any audio system.

+++++ " First of all,to flatly mention that two are automatically the way to go is just wrong... " +++++

this kind of statement has no single support ( real ) from your part.

I don't want to follow this " dialog " because your non know-how about only could confuse to other people and IMHO can't help to any one, I'm sorry not to have the right " education " here but I can't explain it in other educated way. Please don't bad feelings, I respect and you have my appreciation.

Regards and enjoy the music.
Raul.

"I don't want to follow this dialog because your non know-how about only could confuse to other people"....Raul,you're lucky I have always liked you so much!

That is "exactly" how I feel about "your" input on the subject, as it relates to "my own situation".So we do agree on something!Let's agree to leave it at that.

BTW,to me,this is just friendly disagreement.

Best.

BTW Raul,my mention of "education" had NOTHING to do with how I perceive your "formal" education.Just your knowledge of all things sub-bass related(we can "all" continuously learn).The business of "distortion" you mention has nothing to do with my application.....I think you are taking this a bit too seriously.
Best.

Sirspeedy...I too am familiar with the idea that low frequencies are non-directional. Absolute BS!