The subwoofers from Bose allow you to enjoy deep bass and have an intense movie experience. Both subwoofers have QuietPort technology that prevents sound distortion, so you can experience your movies and series realistically. You can only connect the subwoofers to Bose soundbars. The Bose Bass Module 700 has a 10-inch woofer that provides a strong and deep bass sound. The Bose Bass Module 500 is more suitable for smaller rooms because it has a 5.25-inch woofer. The size of the subwoofers is the same.