I got in about a half hour last night before bedtime and after the time necessary to do the setup. My AR2ax's I have temporarily just pushed to the wall, so that is not ideal. I am also in Phase I - listening with only the speakers changed. This means I am initially running with the Dennis Had Inspire LP-2 pre and conrad-johnson Premier 11A (70wpc push-pull). I will soon switch over to the 10wpc single ended Dennis Had Inspire KT150 amp but I first wanted to listen with only the one variable changed.
I have the 7A installed as they are broken in. I no longer have a good way to break in the 7F's separate from the system, so I will probably switch over to them after a bit and break them in within the system, then do more of a 7A/7F comparison.
Initial impressions are positive with reservation. I suspect my impression will move more positive with the single ended amp, which is what this is all about. Two qualities immediately were evident, though not unexpected: imaging is more real and soundstage bigger (together, that's one). I'm glad this was unequivocal and lives up to the reputation. The other is the midrange texture. Again, what I anticipated, but very glad to hear it is clearly there. Things like sounds from reeds, guitar strings (plucks and finger squeaks), voice and breath, are all more present with more facets to each sound, ie, "texture".
I am surprised at the quality of the bass. Playing without subs, it is clear that the bass range is there and with nice articulation, just not as loud as with subs or as the AR's without subs (three way with 10" woofers and known for good bass response).
The 7A is the alnico magnet with whizzer cone. Overall, there is a slight softness to the sound. Though when I listen in, I clearly hear details. That may just be something that is different and I can't say better or worse than I am used to yet. The other is a very slight edge that I didn't have with the AR's. They may need a bit more break-in and/or may need the single ended amp to really settle into that "just rightness". I am curious about the 7F's now as they will likely come forward a bit more, hopefully without any more edge than the 7A's.
Another factor, similar to my hopes with the single ended amp in the mix, is the right tube mix. I have done tube rolling tailored to the AR's and switching a tube or two may make all the difference in that slight edge. One more variable to try is blocking the port. That very well make some difference in the areas of my reservations. Given that I use two quality subs, this is a viable option.
The bottom line is that I am not at all discouraged by these caveats and greatly encouraged by the immediate improvements.
If you want some Omega porn (sorry Louis!), below are some photos of the unpacking and setup thus far. You can see my AR's pushed back. The red pieces are the Inspire LP-2 preamp and KT150 amp. Way over on the right is the CJ Pr11A and a Thorens turntable. Left side of the console is a Cary SLP-05 pre. Right side is an Onkyo 5508 pre/pro for the home theatre and for controlling the subs when in two channel mode. Source is a Cambridge Stream Magic 6 streaming flac from a Synology NAS. The streamer has their DAC Magic Plus built in. I've liked this DAC over several more expensive I have auditioned at home included W4S and Bel Canto 2.5. There is also a Sony BDP and a Dune Smart D1 that are mostly used for video.