I recently purchased a pair of B-Tech BT77 side clamping speaker mounts and I'm pretty happy with them.
I was impressed by the build quality when I unpacked them. These are well made and sturdy. They say they can hold up to a 55lb. speaker. My HVL-1's are 12lbs., so no worries there. I feel that these mounts could hold a heavy speaker, but 55lbs. may be a little optimistic.
Once mounted, you're able to swivel the speakers to up 360 degrees. You can also tilt the speakers +/- 7 degrees.
Assembly and mounting was easy. Instruction book was actually helpful and well written.
They came with all the screws, washers, and anchors needed for mounting. I chose to use a heavier anchor on one side because there was no stud. They come with a few pieces of sponge like fabric to apply to the clamps so you don't scratch your speakers.
They come with a cover to put on the rear bracket to hide screw holes. This is the one thing that I found disappointing. I thought the cover would 'snap' into place on the bracket but it doesn't. It 'fits' but does not hold well and vibrates. I'm not sure if this is a design flaw or I missed how to properly install the cover. I used two small pieces of scotch tape, top and bottom, to hold the cover for now until I can figure out what to do.
I recommend the B-Tech BT77 Side Clamping Speaker Wall Mounts. Well built, easy to assemble and mount, and a Medium WAF rating.
http://www.btechavmounts.com/product-range/products/bt77
Barry