I don't have a blog to post anything... but I was there just before Ked.
I've mentioned elsewhere to some degree. But I'll vote for what Ked has said, other than switching between cartridges (we didn't do that).
Mike has the most complete setup I've ever heard, by a long ways, as it leaves less to desire than anything else I've experienced. He showed me the way he's tuned the room up, like with getting rid of the 30hz suck, and treating small high frequency reflections off of the surfaces. That's on top of the room that was designed with intention. It's undeniable that the cumulative effect is the best soundstage I've sat in front of, and most visitors will ever get to. And when I say soundstage, I say it in the way Ked has talked about, where every little thing is very distinct in it's place. It is not just a direction in which you hear it if the recording tells otherwise. For example we listened to one of my copies of The 4th & 5th Brandenburgs (TMG) and it was very evident of all the players standing next to each other, specified you might say. At the same time you can hear when something is very deep, far away, it's incredible and hauntingly cool in some recordings.
To try and compare to other things, and look past the cohesive amazing setup;
Do I think Spectral's would sound faster? No, not in his barn anyway. First I want to mention the Dartzeel's play complete notes, where as Spectrals tend to have a little sharper attack and decay but in the middle you're left with a somewhat empty note. That might change with the factor that leads me to believe that the speed would not be faster, systems based around the Equitech balanced transformer. I've heard Spectrals and the Dartzeel on them, and by zero means do I believe the Spectrals sound faster. The noise level was low, but trying to recreate some of what I heard (a multiple places) I think Equitech's have a minor issue with storing energy that holds back the peak speed, soften things a little, and some (and/or hence) timbre. It's a little unpredictable what different equipment may be like in response to their use, for various reasons. This is directly in line with characteristics you see in other transformers (well, I do) when designing gear.
The GG sounded better than I expected. At shows I've never liked it. It doesn't do PCM as well as some other DAC's I've heard. And I'm not sure that climbing up the DSD numerical values added enough for me to really get excited about (some just sound soft to me). But overall it didn't sell you short on anything. It has a great soundstage, it has dynamics, it has some timbre, on and on. It would be neat to hear the upgraded version, since it was already very good. For the sake of convenience I don't believe Mike is selling himself short on his system when he likes to listen to digital during his own sessions. While the vinyl is better, without a doubt you get to enjoy the splendor of his room with digital within a difference that is negligible if you just want to sit and hear music. There's times where I don't feel like flipping discs, so I greatly understand.
While the Dartzeel's seem to do things many - and I do mean many - amps cannot, they are not perfect either. I think they reflect the experience very much so, because they don't stand out in any particular direction so they're actually a great choice for many people considering how odd some other amps out there sound. The price tag is high, and to be honest I think it's fair that when you're looking at them you can consider anything at any price range as competition because there's no true reason why something significantly more or significantly less can't be considered "better" to whom is listening. I don't believe price is entirely relative to performance once you get up into a range where the designer wasn't making sacrifices for budget concerns.
Those big 458's certainly take little effort with the music that's thrown at them. When I was there the highest wattage that read on them I believe was 27 watts, and not on a bass line (could have been as low as 24w). What I didn't notice them doing was dynamics. Now you might be thinking I just went off the deep end there... but consider that I refer to dynamics in the sense of the word, not just how loud something can get. For me good dynamics gives you a very visceral representation of the volume changes and solidity to the sounds. We're talking volume in voice, drums, everything. For example in a singers voice the vibrato hinted, it was there, which is more than countless amps can say, but it wasn't great. So overall they weren't doing that at the level I prefer. And the image's solidity were more recording dependent than I'm use to, leaning much farther towards the soft side. Don't get me wrong, the 458's can blister your ears if they need to, and drop huge thunder on you, but just big power isn't dynamics for me. I feel as though there may be some more potential behind them, and do actually feel they're a very good choice for many people's taste but not mine personally.
All of that tells me something, being able to read so much between everything, I think the MM7's are an amazing speaker. The Accuton integration is easily the best I've heard because, well, you don't hear Accutons, you hear music. They portray whatever is thrown at them with absolute grace. Their design isn't just for looks, I believe the anti-defraction shape helps a lot in such an immaculate room like Mike's. They probably don't have much for rivals out there. Off the top of my head there's nothing I've heard. I haven't heard Apogee's anywhere notable, and haven't heard VSA's new Ultra line but can say for example the VR-55 using similar Accuton drivers isn't nearly as well integrated. (this isn't a problem of having less drivers, which obviously drops the price a lot, but more about crossover etc). If there is one thing I'm curious about it's the tweeter, I'd like to see if it can do bright when a recording wants to be bright (this might be complicated and hard to accomplish, for example due to power, and not limitations of a tweeter). I'm not sure I'd want the sub towers for the really deep bass. I think I prefer a swarm style, and resonations from the turntable where weird at times. I could feel the record playing on certain albums, at a below hearing threshold, and it's not a sensation I would keep if given the choice. Overall the MM7's are super easy to drive and absolutely amazing, beautiful speakers. I've certainly become convinced Evolution Acoustics is a contender with anything else out there, and certainly could be the winner. In Mike's room I think they best every last component he owns, as silly and negligible as that is as a thought.
Now I got to say it too, Mike is such a fantastic host! If you've got an invitation pursue it, you'll have a lot of fun. Mike is absolutely pro at finding albums in the dark, and bringing cut after cut of great music. I took photos of several albums with my phone so I could get them later. He went a bit out of his way the first night for me, as he just got in from a flight, and I do so appreciate it as an experience cemented in my mind.