No it is not a servo sub, however in it's sealed configuration. It is a very tight, acurate and musical subwoofer, especially considering it's price point. I purchased this from GR Research about 6 months ago. Sometimes I use it with my computer setup, no crossover as I'm running my mains directly to each amp and then to the computer, so it's running full range. I know it's not the best method to run a sub, however it will do until I get a pre with crossover or a sub that will control crossover by itself utilizing the LFE input! Operating full range from the P.C. does not seem to take away from the S.Q. of my main speakers but I use the sub at very low volume.