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

[Don Quichotte]

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 here and here, respectively, 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!

 

[ttocs]

Hello, and welcome!

It's really impossible to hear all the good that can come out of these speakers without many more hours of break-in. I actually logged the break-in of my 13A's and it wasn't until after over 50 hours that the improvements were becoming less pronounced, but continued well after 100 hours. You can read the log here if you'd like.

The powered woofers in the 11A and up are a must have for me since my ears first heard them. If you setup another audition after the 11A has many more hours on them I think you will be amazed at the difference, and I am confident that your list of drawbacks will disappear.

 

[Don Quichotte]

Hi! Thank you for the welcoming and the reply. I've read your thread with great interest and, while it describes significant burn in changes, I'm not sure hot to relate the changes you mentioned with my concerns. Would you say your 13A became meatier, fuller in the lower mids and bass and livelier and more dynamic overall as they were burning in or not really? This is the direction I'd like the 11A to be turning in. Also, can I suppose the 11A and 13A, at least, have very similar voicing? Finally, have you heard the Classic 9?

 

[ttocs]

My previous speaker, Vista, had a 9" panel and a single ported 8" woofer. The Classic ESL 9 is what I consider to be a great upgrade to my old Vistas. While I did hear the ESL 9 several times it was not in direct comparison to the 11A so I can't directly compare with an apples to apples experience due to different rooms/amps, and I had already made the decision to look specifically at the 11A. So while I know the ESL 9 is much better than what I was used to, I also knew that the 11A was the one for me. Or so I thought.

After several months of thinking about and auditioning the 11A, I loved it, I bought it, all while purposely not hearing the 13A because I really didn't want to be in a position of convincing myself to spend the extra money. While I still had the invoice in my hand I asked the sales person a couple questions which led to needing to listen to the 13A to best answer one of them (you see? I was already doubting my decision!). After 5 seconds of listening to the 13A my brain had a heart attack knowing I needed to change my order. I listened for only another 20 minutes to conclude that I needed to cancel the order for the 11A and upgrade to the 13A. The biggest difference is better bass, and I knew I'd forever be wanting if I had stayed with the 11A. The other differences were not as apparent but noticeable, with the next biggest difference being a larger sweet spot.

Voicing of the 13A vs its smaller sibling? Same but better. Different and better. This gets into the weeds on comparison due to what we each want to pay attention to. Same design but different size for me is same voicing, but then the 13A has a deeper voice.

An easy comparison to me is Classic ESL 9 vs Impression 11A. The major difference being passive 8" woofers vs powered 10" woofers, and when you throw in ARC calibration this turns it into a really major difference! Between the two I wouldn't hesitate in getting the 11A! The 11A is also easier on your external amp due to having its own internal amps for the woofers.

Regarding break-in, I noticed a shrill piercing sounding treble from certain notes from screaming guitar and other similar sounds at certain freqs that began to subside around 50-60 hours, but didn't totally go away until after 130+ hours. So these speakers need some definite time on them to reveal their true sound. The manual I think states around 70 hours, but my experience was close to double that is necessary.

 

[Don Quichotte]

...I needed to cancel the order for the 11A and upgrade to the 13A. The biggest difference is better bass, and I knew I'd forever be wanting if I had stayed with the 11A.

Better as in deeper? Fuller / weightier? Punchier? Was the 11A able to rock with punch, drive, PRAT? (the very often mentioned question about the Martin Logan speakers and maybe other electrostatics too - a question that I couldn't confidently answer in the Impression 11A's case, while the well burned in Classic 9 definitely can rock and be exciting and full of energy when needed) Are your 13A's able to rock (by themselves, without the subs)?

Very useful info you are providing me with, thank you again!

 

[ttocs]

"Better bass" in this instance means deeper, more voluminous.

In my world with my puny brain, a smaller woofer is more punchy than a larger one. So while I can't say for certain any difference in punch between 11A vs 13A, I would say that I don't find anything lacking in bass with the exception of being able to produce the very low freqs below it's design capability. That being said, I have not yet used any subwoofers for two channel listening with my 13A's since I got them almost a year ago. Yes, I would like more extremely low bass to round out my system, but it's not anything of great importance. Just last week I began toying with trying to incorporate my subs for two channel usage but I'm not sure it's going to work out like I would want, we'll see. I only want to fill-in below what the 13A is capable of providing.

Electrostatics are not as "rocking" as cones, but the 13A does a great job of rocking my house when I feel the need for decibels! The danger in high volume with these is that they are so clear and distortion free that it can feel like the volume needs to be cranked higher when in fact it's already very loud! I think the highest SPL I've listened at is a little north of 105dB for a short period of time. Typically in a session I might feel the want for 95-100dB, but mostly it's lower than that.

Please let me reiterate one thing, these speakers need plenty of break-in on them before pushing them to their limits. They simply won't perform as they should until then, and at the cost of these I didn't want to take a chance of damage by being too eager, so I waited till after 120 hours before maxing out the SPL's.

 

[ttocs]

I just calibrated tonight for only the third time so I just had to mention about the results. I'm simply amazed at the improvement! And I was already happy before.

Don Quichotte I'm letting you know this because the calibration feature is soooo nice to have, but it's not available on the Classic 9. This is to say that if you had two identical speakers but one had this ARC calibration feature, I would pick the one with ARC. But the 11A has other advantages over the Classic 9.

But . . . . as with any decision this important you will need to decide what your ears like to hear. Nobody else can make that choice for you. Hearing is a uniquely individual sense.

 

[Don Quichotte]

Congratulations for your improvements, enjoy! ARC being so impressive is very good news. On the other hand, going with the more affordable Classic 9 in my case will almost certainly involve some other kind of room correction later on, probably Dirac as in the MiniDSP SHD Studio, and Dirac seems more flexible and possibly better to me (more customizable target curve and the choice to DSP the panel too should it prove beneficial, without an extra A-D / D-A conversion required). So ARC is not a definitive advantage of the 11A, but other things are.

As for the rock-ability, I'm not really interested in deeper bass or more SPL capability than Classic 9, both of which the 11A should definitely provide, but rather in drive, that foot-tapping (or head-banging ) rhythmic energy that is very much related to the punch, tactility and fullness. I was surprised to hear the 9's doing quite well in this regard, much better than I would have expected from electrostats (even if hybrids, actually), with the 11A a bit boring by comparison (in this regard only).

I'm just being told on another forum that the extra fullness of the Classic 9 would be not because of the burn in but because of the higher crossover point and the passive crossover coloration. Trouble is, I might not be able to audition a burned in pair of Impression 11A and I really like that fullness (not so much the congestion, though, but I can live with that). Choices... I'm not good at this...

I wonder if an official answer from ML would be possible regarding the alleged different voicing of these two models. I know manufactures usually refrain from making very specific or comparative comments on the sound of their products, but then, I have nothing to loose asking...

Many thanks again for being so helpful. I'd be grateful to other ML users should they chime in with their opinion and experience just like you did.