AVALON OWNERS...

Any spike protector discs will work as long as you keep the
speaker height similar to for the downward firing port. Different cones
will have slight sonic differences, but
relative to cost those differences are rather small.

If cost is less of an object, you may wish to try Finite Element Cerabases or Cerapucs which would not require
spikes, cones or protectors and still keep the speaker base height similar to stock and protect your flooring at the same time.

RFG

Actually,my speakers came with really nice "gloss finish" brass cones,which look rather pricey.I do like them,but would not care for a generic steel type.I was just curious.
However,and follow my logic,I believe if one can add more "surface area" to the part of the cone,which comes into contact with the speaker bottom,that would be a good thing.My cones are quite wide,but I have seen some new types(I forget where)that look to have massive width.Probably costly,though.THAT sort of intrigues me.
The other solutions,though probably just fine,don't seem to fit my application,being that I am on a rug/concrete floor.
Best!

In addition to more surface area at the interface, what if you also screwed the feet into the base of the speaker using 5/16th inch threaded rod for a rigid and very solid connection of speaker cabinet base to foot? That's how mine are designed to function.
.

Rushton,great idea,but I am such a fanatic that I don't want to take a drill to my speaker bottom plates.I like the more massive contact area,yet your idea is better for most folks.

You can lead a horse to water but you can't make him drink!Cheers Dennis