This is going to sound stupid but hear me out.
There is an exposed steam pipe in my apartment that is used to supply steam to the building's radiators. It is not insulated and gets pretty hot when the heat is on. It's about 3-3.5" in diameter
I am thinking that I could buy a regular speaker mount and secure it to the pipe with hose clamps, then mount my ~14lb surround to it.
Obviously I will not be drilling any holes in anything, the hose clamps will go around the plate of the speaker mount to hold it up. notcrazy.PNG 5k .PNG file
I have two concerns:
1. would this put too much strain on the pipe?
2. would the heat transfer through the mount into the speaker?
I suppose I could mitigate #2 by putting a layer of insulation between the mount and the pipe.
If the mount is metal, then it's most likely going to conduct the heat over to the speaker. Also, if you're worried about weight, then I'd also run some kind of support from the top of the speaker up to a joist or something in the ceiling. This will help minimize the load that the pipe is carrying. To answer your other question, some pipe insulation should help reduce the heat transfer.