I know you posted your questions couple weeks ago so apologies for a late, but my thoughtsโฆ
I had 28s hooked up to a Theatre and they were phenomenal. ย I was actually very impressed by the soundstage and the clarity. ย Especially if you have the room to give them extra distance, paired with the Theatre it can give a pretty immersive front soundstage. ย I have a relatively open room and no wall whatsoever on one side so I really did not get any side or height effects from the Theatre that were substantial, yet pairing with the 28s brought out a lot of that front soundstage.
Now to be fair, the processing in the Theatre has a lot to do with that. ย Although I do think the Theatre is priced excessively (โฆand this is coming from someone who own 50s and I one hundred percent do not regret the cost), the quality and performance of the Theatre is pretty hard to argue. ย Even the bass of Theatre can give some low extension when it needs to. ย The calibration and the true image processing really does add to the โdimensionโ of the soundstage.
So while I have never owned 18s, I have a feeling the Theatre would bring out a lot in them. ย I have heard from two different people that they feel the 18s sound better than they did before when hooked up to a Theatre. ย That said, they do not have the punch of the 28s and give a little less of a presence, but I would say top end clarity is slightly better.
โ>The 28s also have drivers that are somewhat side firing. ย Especially given the ability of the speaker to calibrate (realizing that B&O does not just alter the EQ curve, but can individually adjust drivers), that can make a big difference in certain rooms, and it also can impact the soundstage. ย I think this is probably what gives the 28 a very wide soundstage in a movie application.
NOTE: ย I am primarily talking about movie watching as from your post I assume that is the intention for swapping and upgrading. ย My thoughts would lean differently if this was commentary on musicโespecially given certain genres.
Ultimatelyโ> I do think the 28s lack not so much the depth of extension, but the power in that extension IF your room is a decent size OR you are someone who really likes to โfeelโ bass. ย Mind you, for music I would never want/need more bass than the 28s offer. ย But I am also not a bass heavy person. ย However, if you really want to shake some furniture the 28s are just not going to do that.
The 19s will not just give you stronger bass, but realize that on surround tracks there are specific LFE channelsโฆeven if the 28s matches in bass output, having a dedicated sub offers more. ย Then too, you gain the freedom to place the subwoofer wherever best, as opposed to the 28s where their bass woofers are locked to the position of Front Left/Right (although!โฆthere is an advantage of having the bass more spread out by having the two woofers in the 28s, so that advantage really comes down to knowing your room). ย ***The 28s will most likely give you โbetterโ bass in terms of strict quality presentation, but the 19s will be more impactful. ย I am assuming a lot (my apologies) but it sounds like you will probably be more pleased by the presentation the 19s offer even if technically the 28s are acoustically superior. ย (Remember that part of enjoying sound is personal preference).
If it were me, I would go with the 28s. ย However, that is sharply flavored by the fact that I REALLY like the sound of the 28s (and comparatively, I appreciate but am not the biggest advocate of 18s). ย ALSO, I am making a suggestion under the assumption that you can comfortably afford any of the options you posited. ย I say that not to be rude, but as with most things, I think the enjoyment proposition changes based on the perceived value (even if that is more an emotional argument). ย The 28s will cost you twice the price and only you can say whether you think you are getting twice the price (or better worded, โtwice the enjoymentโ) in performance. ย If you are already spending that much, I would choose the one I think I would appreciate, BUT again if these really are a stretch I think both will be great.
As far as purchasing demos, my 50s were demos. ย They looked brand new and I have never had an issue. ย If you are comparing the same exact options I would say demos are a safe betโฆ..this is not like buying a demo iPhone from an Apple Store that has been slammed around. ย I assume they are handled with care when set up and taken down, and k assume people barely touch them when in store. ย HOWEVER, if you are being forced to compromise on color options just to save the money, personally I would stretch and get the color I wanted. ย You are already spending a ton, so spend a little more and get what you want especially for something that will switch you for ten+ years. ย On my side, it just so happened that the reason I went with the demo was because it was the color I wanted and ordering that specific option was longer of a wait than I would have preferredโฆso I jumped and am completely fine versus having waited and bought new.
Hope that helps!!
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