I designed this since I wanted a way to keep my Sonos Sub off the floor to make it easier to clean and vacuum around it. The Sonos Sub weighs about 35 pounds, so I wanted to make sure that I wouldn't find it on the floor in the morning. I did do some very basic loads analysis for a cantilever beam, and if properly printed with the right materials, one hook by itself should be sufficient. That said, I also created the bottom hook which helps keep the sub more stable on the wall and provides significant redundancy. The hook and bottom brace are designed to support it by the thick frame of the sub and do not interfere with the moving speaker parts in any way.

HOW DOES IT WORK? Fantastic. The mounting creates a slight gap between the sub and the wall which allows you to use a thin profile extension cord behind it like I've done. Even if you don't mount it near a power outlet, that air gap between the sub and the wall seems to greatly impact its output. I had to turn down the bass boost from +5 to neutral and even then it will rattle your fillings.

To print, orient it on the side with an FDM machine or with structural resin. This will ensure the layer lines are perpendicular to the load. If oriented with the back (the side against the wall) on the build plate, then your layer lines will be parallel to the heavy load and this can lead potentially to issues.

I would also highly recommend using PETG or nylon for FDM Printers. PLA or even PLA+ can have odd creep and fracture behaviors under heavy loads.

I would not mount this using drywall anchors. I recommend mounting this only directly to a stud with sufficiently long screws. The simple way I found to mount this was to do the top hook first and then hang the sub from it. Once you get it straight and level, you can place the bottom brace underneath the sub and it'll basically be pinched in place. You can then mark the proper screw holes and finish mounting it.