The bottom part of the stand is made of two parts of wood. A base and a trim cap. I cut a clearance hole in the base 3/4" plywood large enough for the threaded flange area of the black iron bases. I also free-hand routed a 1/4" relief in the bottom of the 3/4" plywood base. I wanted to mount the black iron base to the bottom of the plywood to hide it. The 1/4" relief was needed so the black iron base would not sit on the floor (see the first photo). The 1/4" plywood was made slightly smaller (for looks) and I drilled a 13/16" hole in the center of it. This diameter allowed for the pipe to fit tightly in the hole which supports the pipe and made the look real clean.

Size the tops to fit the speaker you want to hold. Adjust the scale of the bottom accordingly. I suppose you could scale the pipe up to 3/4" for larger speakers. You could even combine three pipes for a real substantial look for larger stands. I simply surface mounted the other black iron base to the underside of the top plywood piece. You could improve the look by relieving the bottom of the top plywood piece and allowing a flush fit. Given these stands are only 24" tall (or so) you don't notice the upper black iron base. I also drilled a 3/8" hole in the center of the upper plywood piece to accept the speaker wire. I like the idea of running the wire through the pipe and out the bottom.

Add 4 nail-in hard rubber feet for the each bottom and 4 small, clear rubber bumpers for the each top (to provide clearance for the wire under the speaker). Sand 'em, relieve the edges, spray them and your done.