The purpose of the KRK subwoofer is to extend the bass of my pair of Adam T5Vs. This combination is mainly used to listen to blues, pop and rock music. It is connected to a Volumio media player with a high end DAC. The T5V has a nice bass of its own, but I wanted a subwoofer for that extra bit of bass, mainly reproduction of bass drums and the lowest 4 string bass tones going as low as 40 Hertz. I choose the KRK S8G4 for its compact size, multiple inputs including RCA and the selectable crossover frequencies. It works fine for me, but have a look at the bigger sized KRKs if you want to hear synthesized bass and movie sound effects. In addition, the optional foot switch to bypass cross over really helped me to adjust the subwoofer. Finally, shipping from Thomann is really fast.