Marigo Lab/The Cable Company Dynamic Driver Bands:

Some of these brands and products are a bit confusing in terms of their origins. The Dynamic Driver Bands ($39 for a set of four) are not on the Marigo Lab website, but it’s listed on The Cable Company website. This product improves woofer performance by tuning the woofers’ resonant frequency. The bands are also said to dissipate the energy of vibrations to help the drivers work more harmoniously.