Good listening distance between ears 👂 and the speakers?

[rwnano]

There's a range that speakers are effective. Bigger the speaker and the range at which it has the designed frequency response for the listener usually starts further away.

When shopping Genelec speakers, they give a distance -- https://www.genelec.com/correct-monitors

The explanation is around the summing of multiple drivers. Reverb factors in as well.