Speakers with the most detailed midrange? (non-ESL/planar)

Klipsch Heresy IIIs somehow get midrange right with their 1.75" titanium diaphragm driven horn. I was surprised by this as I'd never previously owned a horn speaker for my hifi rig needs, but there it is. These things are relatively inexpensive for a USA made item, and in my ever humble opinion are way underrated world class speakers. I use these with 2 REL subs that do a great job of fooling me into thinking I'm having more fun.

@gosta -
The Kii Three wouldn't have the SLP capability I'm looking for unfortunately. From what I've read about the Dutch & Dutch they are a bit shy of the ATCs in mid detail. The big attraction about them is their ability to adjust to rooms. Cardioid bass etc. I know you can't go on what you read but I find its a good starting point to reduce the amount of speakers one has to audition. I would still like to hear both of these.

You make an interesting point on the Unity Audio Boulders. I think perhaps the room I heard them in was not treated well as the bass was a bit too much and the mids were very obscured. I was very disappointed. That mid/tweeter coaxial driver is certainly interesting. Elac uses it in some of their higher end speakers. I've never heard those.

If you ever do A/B compare the Lipinski to the ATC, please let me know what you think. I would be very curious of the outcome! Since the Lipinski is based on the Dunlavy/Duntech design, it really is a world class speaker. Do you have the yellow cones or the newer upgraded black cones? The newer versions have thicker and larger cabinets for better bass. They also claim a smoother midrange, but I'm not sure how they achieve that. Perhaps an upgraded capacitor in the crossover. I think a pair of Lipinski with a sub or two would be fantastic. In a two way design, I'd be concerned about the distortion on the mid frequencies at higher volumes. 

Regarding smaller speakers in conjunction with subwoofers, I'd be curious to hear the Magico Q1 as well as the newer Paradigm Persona B with the beryllium drivers (!). Personally I refuse to pay the money Magico is asking for the Q1 for bookshelf speakers but I would be curious to hear them and see how detailed they are compared to ATC. The Paradigms seem very interesting, unfortunately they are ported bass reflex designs. I can't deal with unfocused bass. One trick I have found useful to bypass the bass reflex design is to crossover to the subwoofer at a higher frequency than the frequency the port is tuned to. I did this with my Dynaudio Air20s and the bass tightened up drastically.

@gosta 

You may also want to check out Accuton driver based speakers. Salk uses them. I've heard fantastic things about them. Supposedly the newer drivers aren't as fragile as the older designs. There is also a driver from Raven that looks interesting. I believe Nola uses them:
http://ravendesignstudio.com/line-source/
I'm just a bit wary of getting too much into obscure drivers and speakers. 

I'm also curious to hear the ESS speakers with the Heil AMT.

Thanks for your detailed response and information!

@shadorne 

I have read that the new ATC tweeter is a great upgrade. I can certainly see that, as the only real shortcoming I found in my SCM100's were the high frequencies displayed sibilance and they lacked air (rather boxy sounding). This caused a bit of a dead sound. I'm really curious to hear the upgrade.

@woofer72

Not sure what you had in your old SCM 100 - there have been several tweeters over the years. The old Excel millennium tweeter was excellent - one of the best. The older vifa tweeter was sibilant but my quite old pair of SCM 100 may have lost ferrofluid (it dries out after a few years hard use with any tweeter). Not sure about the even older Audax...

The newest tweeter just integrates perfectly. It has no ferrofluid. I no longer think about a tweeter in a separate way like you would do with other two ways or three way speakers. It just sounds like sound even if your eyes know there are three drivers there ...the sound is just completely integrated.

I guess the tweeter was the last thing they eventually had to build in house to get the kind of quality they require. I find it surprising they could do better than Excel Millennium. I think it took ATC about 10 years to develop so it just shows you how very good Excel/SEAS products are!