The sub isn't to make the overall sound louder....but better..

That Mackie 150 goes down to 100...that is no bass response for music..The S950 maybe goes down to 90..those 10-12 people aren't hearing any bass...just you the player..and it is still poor, but you are use to it..

A sub just makes it fuller, you don't have to thump it...just get under 50 for real natural bass range..