spikes keep the cabinet from moving as well ,but the vmps rm40's are heavy enough(they are not going anywhere) that you don't need them. their bass drivers are designed to work with the floor much like some loudspeakers are designed to work with other room boundries(cornerhorns for example). sometimes after listening to lots of speakers that don't have the ability to reproduce real bass,our ears become trained to except higher frequencies as bass...if you're not 'feeling it' as much as hearing it, the speaker isn't getting those deep notes out...the vmps however should play those lowest registers effortlessly.