I have two SVS Ultra 13subs with upgraded plate amps and now I can control all the settings on the subs through the SVS DSP app on my smart phone My tower speakers have built-in powered subs also, I have my SVS subs crossed over at 40 hz and sub volume relatively low Depending on what's playing on my streaming play list i will tweak the volume and crossover on the fly It's so easy to return it back to the original settings