I just purchased a slightly used original Martin Logan Dynamo Sub for $275 from a guy that use to work for ML. It is going to replace my older Velodyne ported CHT-8 sub to run with my Maggies. The Dynamo use to sell for $700. I wanted a more musical non ported sub. I don't need thunderous bass, just something fast and musical to integrate well with the 1.6's. I will cross it over at about 45Hz.