Martin Logan SL3 missing soundstage

I have bought a used pair of Martin Logan SL3 with completly rebuilt crossovers and fully rewired with Kimber silver cable inside; I changed them over my SF Grand Piano Home and I think they are great speakers but I can't get a decent soundstage at all.
They sound very flat and two dimensional compared to the SF.
When I audition them they were connected to Gamut gear and sounded very, very nice, nice soundstage as well.
My room is 12feet wide and 16feet long; the speakers are positioned on the lenght side of the room.
They are appox. 2feet from the side wall and 3feet from the front wall, 7feet apart.
The room is with carpet.
I tried many positions and I can say that the ML are very sensitive to positioning, but have you got any suggestions on how to improve the missing soundstage?

I have heavy curtains on the back and my setup is:
CDP - Musical Fidelity KW DM TR+DAC
AMP - Primare A30.1
TURN - VPI SCOUT,Ortofon A Cartridge
PHONOSTAGE - Eastern Electric Minimax
INTERCONNECTS - Van Den Hul The First, Zion silver
SPEAK CABLES - Qed xt 400, biwired
ISOL8 main conditioning
I owned the SL-3's for nine years and it sounds like you have the speakers set up guess is the solid state amplification is the culprit on lack of soundstaging unless you have the equipment rack or big furniture in between speakers...unfortunately those speakers require a high current amp with lots of muscle so you can't go tube integrated but a tube preamp will probably give you what you're looking for.
Thanks Larry, I'll keep that in mind...I know that MF makes the KW and it is a tube pre-amp, I have to get to listen to it...
I used the SL3s for a couple of years and I found that if placed right, soundstage was never an issue. I had other issues eventually but soundstage was not one of them. I have noticed that soundstage comes and goes with listening height and how much reflection comes off the back walls (both the ones behind the speakers and the ones behind you), which means you might want to either try to put something behind the speakers which will dampen or break up the backwave, or move them a bit further out. On the height aspect, I noticed that based on my particular listening position, I had to have the spikes on the back a bit longer than on the front (to tip the speaker a bit more vertical) in order to make the treble come out right. May have been because I was both seated a bit far away and my sofa was positioned quite low.

OTOH, Larryken might be right on solid state amplification having something to do with the impression of flatness. I never did like pure solid state with them. The closest I wanted to get was either hybrid or the InnerSound ESL amps, which were quite good with the SL3s.
move around for best results. amp is not an issue
"I have heavy curtains on the back"...

Do you mean behind the speakers? If so try taking them down. You should not be deadening the back wave from your speakers. Diffusion/dispersion is what you are after. You can use something else to disperse the back wave.

FWIW in setting up dipoles/panels/electrostats 3ft into the room is not going to give you optimum imaging. There will not be enuf delay between the original signal and the back wave signal. For this reason 5' is usually optimum.

Can't tell where your listening position is but I assume it is triangulated and about 7 to 8 ft back from the plane of the speakers. If you put the speakers on the short wall out into the room about 4 feet, about 8 ft apart, and your chair about 4 ft from the wall behind the chair, with a dispersive materiel on the wall behind the speakers, you should get great imaging.

I realize you may have decorative/domestic considerations, but I think think might be a set up that would work well if you could do it (or at least try it).

P.S. I don't think what you describe has anything to do with equipment. If you had good imaging before you should have it again, even better, not worse. Note I'm not saying you can't get better imaging with better stuff, but if I were you I wouldn't go there until you have optimized set up. Stats and panels can take a while to set up properly. It took me nearly a year of playing with Quad 63's 'til I got it right (mostly due to inexperience and a lack of good advise from others).
I think you guys are right in many respects; I have been moving the speakers a lot today and I found a better balance today.
I probably have to move th room around a bit a I can't move the SL3's more foward than 4feet from the front wall.
T-bone, I have the sitting position close to the back wall and when I move my head forward imaging becomes marginally sharper; unfortunaltly I can't move the sofa yet so I will try to put something behind the back wall as it is bare naked.
Newbee, yes I have heavy curtains just behind the wall, and a niche of aroun a foot and a half going into the front wall all made in wood, where the windows lay.
I believe bad reflection is occouring just now, I mean imaging-wise; sound quality is very good just a bit bright but I can live with that.
By the way, got a new interconnect from Townshend Isolda DTC100 and made a good difference, SL3's image a lot more freely.
Will keep you posted and I will upload some pictures in the future.
However if all of you guys have got more tips please let me know.
I would suggest playing with the relative and absolute phasing of the speakers by swithching the leads from the speaker wires accordingly. I've experienced the zero soundstage phenomenon with multiple systems and found this to solve the problem on multiple occasions.
Hi Siliab, do you mean send the signal out-of-phase?
If so I'll try and I'll let you know, thanks.
Hi Carloscotland,
First switch the polarity of the speaker cable leads for one speaker (i.e. black to red, red to black), and listen for restoration of the soundstage. This will switch the relative phase of the loudspeakers. If things improve, I would also switch the absolute phase of the loudspeakers. This is done by switching the polarity of both sets of speaker cable leads simultaneously. Absolute phase can have a surprising effect on imaging and soundstaging, particularly with systems that are inherently good at it. Hope this helps!
Thanks Siliab, I will try that. I already managed to get something back by moving the speakers more distant from the front wall.
I am surprised how little changes can have a profound effect on imaging.
I still trying to fight against some brightness but I think it is mostly from my system spec.