I was at a friend's place on Sunday to do some measurements of his SVS 16-46CS+. He has a decent size room, about 15x25 with 8' ceilings. He has 3 rows of seats and currently 6 chairs (1/3/2 from front to back). His SVS is in the back of the theater, in a corner.
I don't have the spreadsheets we saved (will get later hopefully), but here are my approximations of the results.
Chair at the front. The approximate db range from the lowest dip to highest peak was 13db. A total rollercoaster response.
Chair in the middle. Virtually perfect, until we hit the 50hz tone and the needle fell 20db! The null began at 40hz and ended at about 63hz. You can imagine how this would sound. Everything outside the null is perfect, then a drumbeat or guitar string hits 50hz and you hear almost nothing.
The third chair I measured was in the 3rd row, right side, nearest of all chairs to the SVS. It didn't have any big dips as I recall but it was peaky at 40-70hz. Didn't sound great subjectively.
Now imagine this is your room. Depending where you sit the SVS sounds like 3 different subs. None of the spots measured well. You would probably think the SVS "is overrated" and would wonder what all the fuss is about.
Before we measured, I listened to the first 3 minutes of Toy Story 2 in various chairs. Some spots had no deep bass at all, others were muddy/boomy, the chairs at the back had some nice deep bass but were clouded by the 40-70hz range, the front chair just sounded lousy (see the rollercoaster curve approximation).
Actually measuring and seeing a plot is invaluable and IMO, absolutely required for anyone with a decent sub. Our next line of attack will be to test different sub placements as well as adding a 2nd 16-46CS+ and a Behringer FD to help smooth out the peaks once we find a good sub position.
