This is actually pretty easy. In order to wall-mount a speaker it must use a bracket that attaches to the speaker, which in turns mounts to the wall. Or you put them on a shelf. It’s as simple as that. You don’t want to drill into the speakers, don’t want to use a shelf, and don’t want a solution that uses a clamp, so I’m not really sure how you expect to accomplish this, or what you expect from us, as you’ve ruled out all the options. It’s kinda like saying “I want to go swimming but I don’t want to get wet” or “I want to go hiking but I hate walking.”
Regards,
Wayne A. Pflughaupt