I've got a 12" harmon/kardon sub connected to an AVR125 amplifier also made by HK. I'm playing the music from my laptop-to-amp-to-sub, so I can add decibles on the amp and my laptop. Then I can turn up the Subwoofer Level on the back of the sub. How far is it safe to turn that up? How much bass can I add before I'm going to wreck my equiptment? Considering out of the $6,000 I spent on my HT, about $2300 of it was the Sound System. All together, it includes.. HK AVR125 Amp HK 12" Sub 4 Large HK tower speakers and a HK center channel. I'm pretty new when it comes to dealing with this type of hardware but I know what I'm doing as far as the laptop fine-tuning aspect goes. Give me your advice!