My subs behind my mains and TV in a corner on the left side of the room, I have to move the right main then navigate through all the wires, lean the sub up forward away from the wall so I can see where the volume is set on the sub, using a flashlight because the lighting doesn't shine well in that corner and the line on the volume knob is difficult to see, I guess you get my point
But I understand what you are saying because it seemed to me like something was off, as I was turning the db's up on the receiver for the sub it seemed like the tone was getting much louder without the SPL making great gains and the needle starting bouncing alot. So tonight I'm going to get back there and recalibrate starting with the volume on the sub at the 8 o'clock position and see what happens.
