Sound Stage and Imaging

@grislybutter "254 Hz is middle C! 350 Hz is well into the mid range. RAISE THE CROSSOVER POINT for the subwoofer" The Nautilus 804 has no subwoofer, just 'woofer'. And small ones to begin with, so 350 Hz does NOT sound like a very high frequency for a 165mm cone (in fact the true MIDRANGE speaker has about the same size !!! playing all the way to FOUR THOUSAND Hz!)

And messing with the crossover of a fairly successful commercial speaker is "dangerous" IMO. The I'd rather do a full DIY and safe a few thousand dineros.

Tekton: before the current B&W Nautilus 804 I had the Mini Lore (bought after in house testing several others in the large room with sub). 

Vandersteen: friend has a set of 2c (3 way IIRC), terrible room/setup. But will pay more attention next time. First time casual listening, I liked how 'easy/natural' they sounded. 

IMF 100: can't seem to find in the US. But seems to be one of many LS3/5A based monitors (which I have heard good things about in past readings). What are notable LS3/5A (bang for buck) offers?

magneplanar: unless recently rebuild, I don't want to deal with the potential issues. Locally listed is a pair of MG1. Also MG1B.

Do Magnepan (1.6 local) fall in the same category? 

Martin Logan ESL (local used), Best Buy ESL 8"?

Martin Logan Aerius?

Also of importance to mention: low bass is covered (Velodyne DD15 small room, Dayton 18" sealed driven by ED LT1300 in large room). So NOT concerned in this area.

With soundstage and imaging in mind, what helps with regard to the room:

a) hard vs soft BEHIND the speakers

b) hard vs soft OPPOSITE the speakers

c) hard vs soft SIDE of speakers

d) close or far wall   behind

e) close or far wall - sides

f) close or far wall - back 

Where 'hard" is reflective, non absorbent. 

Where for now to start NOT dipole, etc. speakers. 

Generic or General statement (each speaker is different, but some general rules apply). 

Have never heard Ohm.

Vandersteen 1 and 1b locally, worth looking it?

Lower end Magneplanar or Best Buy Martin Logan?

Also as far as imiging is concerned: aren't the single speaker Kef 150 also known to produce excellent image (maybe not a wide soundstage, and may not 'sound' as nice as otheres (or may concerns, not enough AREA to 'fill' the big room, but maybe enough for the small 20x20?). 

ADS "or pair of ADS L2020s, (which will fill your huge room) and / or ADS L1530s or L1230s. ": can't even find a PHOTO online of ADS L2020. The mid size LDS (L880 etc) look nice (I do like dome midrange, have a pair of Infinity Quantum 2 in parts in the basement, never heard them (no time to go over them, redo xovers). 

Can someone linke to ADS L2020?

Harbeth P3: did they get a bulk deal on screws? Or are they just try hard to make the front as ugly as possible?

I do like the idea of small (2 way or even single) speaker since I am "sold" on subwoofer (even my Nautilus 804, surely not considered being 'weak down there' benefitted from the 18" sub helping under 50 Hz).

@grislybutter thanks for the list/table. I am benchmarking against my Nautilus 804.

And which CSS are you referring to? the one in the table CSS Criton 1TD-X?

@mijostyn I was partially kidding with the screws. Just a bit unusual to see them as exposed as they are in any speaker over say $100 pair. Most would make the REAR panel removable (with 'under' mounted bass driver). 

Kits: not afraid at all. build quite a few back then (very nice finish Eton 10 (in the 80's; GREAT sounding Focal Onyx (still dreaming of it, actually though about recreating it). Recently my sub: https://drive.google.com/file/d/1HPeV4E7xUvmPwq5cBFlI633_yk-dXJy2/view?usp=drive_link

@grislybutter just checked the specs of the 2TD-X. Rated at 100W.

As with every small speaker: do they have enough (even with help from big sub under 50 or (pushing it) 80 Hz) in them to fill a large (volume vise think 40x40x10) room with 100+ db (think Wagner size orchestra authentic SPL)?

Room size concern: I am currently running my Nautilus 804 as SMALL speaker with lowest sub crossover my receiver can offer (50 Hz). Her two 16.5 cm low woofers cut at 350 Hz, and the large mid range runs from 350 to 4k. 

Too much thinking/evaluating options. Had a pair of local Vanderstein 1 slip by (gone now for $250), not sure if that is a loss. Friend has 2B, but not suitable audition room, but sounded 'easy', 'light', 'airy'. 

@grislybutter reading up on SL6 (SL6s? SL600). Also Thiel CS1 (xxx) mentioned in this context. Opinions?

@mijostyn Yes, I run one large subwoofer crossing at 50 Hz, and run the Nautilus 804 as 'small' to relieve from 50 and below duty (also relieving the receiver from the heavy lifting for that frequency range). So the Nautilus woofers only have to handle 50-350. I have found that very beneficial also with other speakers/receivers combinations after initially running the the speakers/receiver as 'full range'  only 'adding' the subwoofer for the low frequencies. 

As mentioned, my single sub is 18". Don't want to trust it to handle 100 Hz (and the Nautilus are not known to be 'weak down low'.

But I have to go high in my small setup with various small bookshelf speakers, some of them do NOT feel good handling 80 or lower (certainly not at higher SPL), so there i need to drive the DD15 sub to 100 Hz. 

@steve59 That is easy: he uses the cheap china pixeldust from Walmart at one time, and the audiophile quality $50k/pound pixeldust the other time. And uses his home made electrical current with ground rod staked into the equator at 11.11 pm on 11.11.

@tom2015 Yeah, those ScanSpeak Beryllium seem to be the cats meow for a 2 way (I have always been a fan of ribbon tweeter, but they need a midrange, no good for under 4 or 5k). PRICEY (and hence the Kismets as well, and not very 'common' therefore no low price used around). 

As far as small bookshelves go, what about:

Dali Oberon 3

B&W 606 S2, 707S

Kef LS50 Meta, Kef R3

Sonus Faber Lumina II, Venere

How to approach the selection? 

See if something of the recommendations shows up nearby that can be auditioned  Listen. If promosing: Negotiate 'try at home' audition or return option. Sell other stuff to finance. 

Even so the (main system) room is huge, the floorplan for the listening area ("room") is not that large (20x20, one side, one back wall). The speakers are located at a 'half' or '3/4' wall, and can only be 2 feet away from that wall). 

https://drive.google.com/file/d/1yRozuEvtpBvvnY4mXcfs0tSG6KmfDYo5/view?usp=sharing

Open baffle speakers: sounds intriguing. Curious: will open baffle speaker with 'normal' subwoofer kill the benefits? Need to look for an opportunity to listen to an open baffle. Might be the effect I remember when I first heard a large transmission line woofer (very natural, deep, airy; I was blown away). 

Just crossed my mind thinking about open baffle and reflecions: how does NEAR FIELD (reflections outside 'ear sensiivity range' compare with respect to imaging and sound stage? Guts feeling: creat imaging (pin point location) but poor 'sound stage' (no artificial 'echo' mixed in to inflate sound stage)?