But crossfeed doesn't widen the channels. That's what I've been trying to say.
What crossfeed does is actually detrimental to the width of soundstage. It tries to converge the left and right channels, so at the end, you have everything layered up in the middle rather than to the two sides.
It's like an in-between of mono and stereo sound.
If you want to experience it, Foobar has some crossfeed plugins that you can use. If you're on a Mac, you can use Fidelia's built-in Headphone FX feature.
What the SF switch does is the exact opposite of what crossfeed would do.
yes, and I wasn't disagreeing, I was saying that the channels widen and end up more transparent, making the illusion of croasfeeded channels than actually crossfeeding them