I started my quest for perfect bass in the summer of 2004. At that time I discovered Ethan Winer's wood DIY bass panel traps and the wonders of PEQ and the BFD.
Long time readers may remember my first bass story here:http://archive.avsforum.com/avs-vb/s...hreadid=422490
I am now living in a new home and working on my HT version 2.0. For this thread, I now want to discuss the miracle of green glue and moving from a single sub to a dual sub setup.
I have a HSU TN1220 tube sub which is now discontinued although still highly regarded. I recently added a second TN1220. I have a parametric EQ BFD (you can read about the BFD here: http://bfdguide.ws/
). I use Room EQ Wizard (REW: http://www.****************.com/roomeq/
Here is my Story in annotated WaterFall LF Graphs. Waterfall graphs show the frequency response with a third dimension time added. With a waterfall graph you can easily see the effects of room modes and ringing.
Attached is my hometheater room, untreated, no EQ and a single sub, measured at my sweet spot (which happens to be in a somewhat bass unfriendly center of the room position).
Notice the uneven response and the ringing of bass especially near my room modes of 20hz, 40hz, and to a lessor extent 60 and 90 hz areas. The ringing is shown as bumps in the plot that extended outward in time towards you in the graph.
Notice the drop out of base between 40-65 hz as well. This drop is likely worsened because my listening position is near the middle of the room.
Looks and sounds pretty poor.