Martin Logan Classic 9 vs. Impression 11A - sound impressions and burn in question


Hello! I have recently had the chance to compare the two models mentioned in the same room / system and my findings are a bit unexpected, hence my post here in order to share them with you and maybe get some help with an explanation of what I've heard. This could have a great importance in the light of a possible purchase decision so please chime in with everything you've got! These being said:

- the 9 were fully burned in, the 11A had maybe 10 hours or so on them

- the 11A were definitely more detailed throughout the frequency range, clearly more relaxed / effortless, amazingly with even sharper and better defined transients, better bass extension and perhaps slightly better highs extension too; they also sounded bigger and everything was better separated, whereas through the Classic 9 things were more... gathered together, let's say (I hesitate to call this "congestion" because this is true only by comparison to the better model in the series, by themselves the Classic 9 have great instrument separation and great soundstage); the bass was also more even and better controlled. The 11A I've heard is clearly the better model from a technical standpoint, no doubt about it, but it is also comparatively a bit drier and perhaps over-controlled or overdamped in the bass, thinner in the midrange, more cerebral and I daresay somewhat less involving

- surprisingly, the Classic 9 also had some advantages: the sound was more tactile both in the bass (a fatter, punchier and more cavernous low-to-midbass injecting better drive into the music, better PRAT) and the upper midrange (some small percussion instruments, I don't know their English name, were more, well, percussive), better emulating that pleasant tactility that is an advantage of the speakers with dynamic drivers; also, they were warmer, more colorful, bloomier (for better or worse), with a hotter (usually for the better, sometimes a bit overdone though) mid-midrange (around 1 kHz I guess) and fuller lower midrange, resulting in a better reproduction of the body of the stringed instruments, the chestiness of the vocalists etc.; probably this extra body combined with the slight "congestion" (see above) made for a more cohesive presentation with better musical flow; hard to describe, the bass, while rounder and more ambiguous, seemed also in a way a bit more natural

Interestingly, Noel Keywood has reviewed both models in  Hi-Fi-World  and in the 11A's review he states that these are brighter than the Classic 9. The measurement graphs at the end of the review shows a significant dip in the 11A's lower mids that is missing in the Classic 9's graph, which overall looks closer to the Harman curve.

So, my question is which of the drawbacks I've noticed in the 11A can be attributed to:
a) lack of burn in (a bit overdamped in the bass, clearly thinner in the lower midrange, less tactility...?)
b) the DSP and A-D / D-A conversion (less natural bass, less involving?)
c) sealed drivers vs the bass reflex design of the Classic 9 (less cavernous, fat, weighty bass?)
d) a different, intentional, voicing of the two models (I thought at least the panels should have a quasi-identical voicing?!)

What changes could I expect with the full burning in of the Impression 11A?

Thank you all!
donquichotte
Yes the comparison was done with same electronics and same room. The ESL 9 with its slightly higher crossover point at 380hz compared to 300 for the 11a gives it a fatter mid bass and more power through the lower midrange because the dynamic woofer is coming into play more. Conversely the 11a will have more detail in that frequency range but I just dont like that panel on the 11a. To thin, to bright. Plus I like the idea of ONE amp powering the whole speaker. With the 11a you have two different loudspeaker technologies going on AND then they put an amplifier to power 300 hz on down. Now you have 2 different amps with their own characteristics and two different speakers ( electrostatic and cones). To much going on. Plus what if the amp section goes out in the 11a. The whole speaker is shot. I just convinced myself of getting ESL 9. Unless you have to money to go 13A or 15a stick to ESL 9 with some good subs. 
You're a very convincing person, I'll give you that :). Happy purchasing and thanks again!
imo, the 11a will reproduce the signal provided by your electronics. they are neither warm or bright. they simply mirror the electronic signal. so if you like warm or hyper detail then choose the electronics accordingly. the bottom woofer compartment of the logans are easily dismantled and any problem with the circuit board ,amp ,woofer,etc can simply be sent back to the company for service.