mzkmxcz wrote: "Soundstage is the off-axis of the speaker."
Well, I have a somewhat different opinion:
A wider radiation pattern results in early sidewall reflections which increase the apparent image width. This is usually judged to be a pleasing effect (according to Toole), but it is not without its downsides.
First, early reflections are more likely to impose colorations and/or degrade clarity.
Second, early reflections tell the ear/brain system that you’re in a small room, and this can constrain soundstage depth and the sense of being immersed in the acoustic space of the recording.
Spectrally-correct late reflections are generally beneficial, enhancing timbre and a sense of immersion without degrading clarity or imposing colorations.
A fairly narrow but well-controlled (i.e. uniform over most of the spectrum) radiation pattern can result in more precise imaging and a deeper soundstage along with better clarity by minimizing early reflections, and if you want a wider soundstage too, move ’em a bit further apart.
Duke
dealer/manufacturer