So I have a Tempest SBB4 ref design I built early this year. I've been very happy with it for HT but just recently I've been listening to alot of music and I find that it sounds a tad bit slow and bloated. I've tried moving the sub to different locations in the room but it only gets worse. I was thinking about changing the port tube length to tune it lower. Will this in turn make it sound "tighter" ? Is there any drawbacks to tuning this enclosure lower, say from 18hz to about 13hz ? I'm fairly inexperienced so I apologize if I sound like an idiot . The SBB4 enclosure is 194L with 64 ounces of PolyFil. Right now I'm using homemade ports made of 3" PVC with flares (using two ports). In LSPCad I'm tuned to roughly 18hz.