Corner speaker placement

You will excite all room axial modes in the extreme LF bass. In the 125 to 350 Hz range you may get some suckout or cancellations from rear wall relfections. You will also get reflections off the side walls which can also hurt the mid and treble response (making sound claustrophobic and harsh).

If you must use a corner then make sure it is not evenly spaced to each wall and consider a PARC.

It is rarely a good location for any speaker unless your room is non rectangular (highly irregular)...although a subwoofer can sometimes work in that position provided it does only the lowermost octave (20 to 40Hz) and is heavily (actively) filtered above this.

Any room dependent resonances tend to be accentuated by corner placement.

depends on the speaker.....gradient revolutions and lots of others, like audio note, klipsch.....like corners

I use the corners I have for accentuating bass. I don't know about all this suck out business, and acoutical confabulation. As far as soundstage goes it isn't great. I use the set up for when I want to hear something on my Klipsch La Scalas loud. At that point subtleties are lost and you are being moved by the music. If your talking about a corner for a refined speaker I have found it doesn't provide anything close to optimal staging, imagery tonal integration what have you, and would avoid it.