I have built a 4 manifold IB system with 2x 18" FI IB3 drivers in each manifold, each (ceiling mounted) manifold is in the corners of a virtual room of my room size shrunken by 25% (width and length). The actual room size is 7'7" high by 22'6" long by 13'1"wide.
Both the front manifolds are powered by an Behringer EP4000 with each manifold on a separate channel and the same with the rear. The receiver is an Onkyo 5009 and each EP4000 is on a separate sub output from it.
I have been running the drivers in with the pretty loud bass tones from a bass test CD and using REWs sine wave function for the past few days. Its pretty powerful;)
Now its time to set it all up. I have had advice to set up each manifold in turn by running the 5009s sub calibration noise through the manifolds in turn and setting the EP4000s channel gain settings so that there is a 72db SPL at the main seating position.
Then i ran a sweep on REW (I am using a 2nd generation Radio Shack spl metre) with the associated .cal file imported into REW and have calibrated the sound card with a loop as instructed.
Here is the sweep with all manifolds on-
As you can see its fab below 50hz but then massive dips. I then did some sweeps with just the fronts and then just the backs running-
And then finally I ran Audyssey and did another sweep-
Much better, but still work to do. Any suggestions? Next step is to run a sweep on each manifold on its own.
Thanks in advance!