If there not too big you can use wall mounts used for plants, I would strap the top part to the wall so it will not tip over.
I have a Yamaha NS-AP7800PNC and I want to mount the 48" tower speakers on my wall instead of using the stands. The speakers do not have pre-drilled bracket holes for wall mounting. Any ideas? I was thinking of having an auto speaker installer take a look.

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