Michael, you might have forgotten I am strictly using a dedicated headphone system. Yes I recommend placing speakers closer together than one would ordinarily think, this is actually the recommendation of the good folks at XLO, Roger Skoff and Keith O. Johnson. The reason for the better sound with speakers relatively close together compared to where a lot of folks might place them - what would you guess, 6 to 8 feet apart in an average room? - is the physics of the speaker/room system. When speakers are properly set up, and I'm not saying all speakers should be 4 or 4.5 feet or even 5 feet apart, it all depends on the speakers and the room, layout, types of room treatment, distance to the listener, obviously. And toe in should not be necessary in most cases, all things being equal, which of course they frequently aren't. Lol. For my system when I had Fultons, the proper distance between them was about 4.5 feet iirc. I am just suggesting that folks rethink the whole speaker placement thing as you might be able to do better. As I also mentioned, or at least I think I did, the best speaker locations in terms of center fill, soundstage, etc. will be found using the XLO Test CD as opposed to the tedious and relatively less inaccurate process of trial and error, moving a little, listening a little.
Moving right along, I am not a big fan of transformer noise and it's effect in the other electronic components and wiring in the component, and cannot conceive why that noise would produce a better soundstage than would the elimination of the noise. By the same token the magnetic field of the transformer impinges negatively on the electrical components and wires in the component and needs to be dealt with to achieve the best results, to achieve taut, dynamic bass, more information and a larger, expanding sphere of the sound. The magnetic field issue can be saved for another day. What I think we are looking for soundstage wise is the dimensions of the actual room or hall where the recording was made, assuming the thing was recorded live. I'm pretty confident all the room echo and reverberant decay and so on is captured on the recording, all things being equal.
Soundstage height kind of comes with the territory, don't you think, the larger the expanding sphere the higher the soundstage and the more you can perceive the sound all around you, perhaps way to the sides or even behind you under the right conditions, assuming the information is on the recording. By the way vibration isolation of the components (I.e. Mass on spring iso system) is quite important for achieving the largest and most accurate soundstage depth, width and height. But a real, live, integrated soundstage, not a projected facsimile of a soundstage.
Cheers, Geoff @ Machina Dynamica
This is a better place to discuss your ideas and not in Room tuning and Acoustics.