Itball's advise matches my very recent experience in setting up a sub with full range speakers in a 2 channel system.
My gut feeling from your description of the sound you have described is that you have set the volume of the sub too high and its output is masking the detail from your main speakers. A cross over setting of 50hz would seem better than 80hz but, I would suggest that you get a SPL meter and a test disc to assist you in both locating the best position for your sub and matching the output levels of the sub and mains. That worked well for me. It only took about 18 hours over four days and a lot of critical listening to dial in my sub (and I think I can still do better) so set up is not a plug and play matter. I wouldn't give up on your Velodyne not would I depend on its automatic set up/equalization system to get the best response.
Hope that helps a bit.
My gut feeling from your description of the sound you have described is that you have set the volume of the sub too high and its output is masking the detail from your main speakers. A cross over setting of 50hz would seem better than 80hz but, I would suggest that you get a SPL meter and a test disc to assist you in both locating the best position for your sub and matching the output levels of the sub and mains. That worked well for me. It only took about 18 hours over four days and a lot of critical listening to dial in my sub (and I think I can still do better) so set up is not a plug and play matter. I wouldn't give up on your Velodyne not would I depend on its automatic set up/equalization system to get the best response.
Hope that helps a bit.