About a year ago I put 2 Fi IB18s in a manifold in the ceiling between and slightly to the left of center in relation to my mains in my theater room.
I'm pushing the two Ohm speakers bridged to 4 ohms with a Behringer EP1500.
At first it sounded really bad and after measuring i found a huge spike that went from 20 to 40 hz or so. Very odd. My ceiling was uninsulated because my roof is sprayed with foam.
So I added insulation to the ceiling and put a BFD on the system and put some pretty big notch filters in to level it out.
This made a huge difference and at first it sounded great, but after having it for a while and hearing other subs I feel it never really sounded as clean or powerful as my previous DIY 300watt 15" sonotube sub. Perhaps because of all of the electronic correction.
So now I'm thinking of either putting my spare sub on my seating area and taking the mic around the ceiling to see if I can move the IB to a better spot.
Or maybe build a ported box stage for my 18's and place the stage under the screen and forget IB.
here are some pics for room layout and IB install.
IB located just left of room center.
14x 18' long room seats backs at 14-15' from screen. columns have 5" x 6' long slit ripped out of the middle of the sonotube to let some sound through to the insulation inside the columns, not nearly as effective as corner wedges but using my old sub and the ears they did help. Please excuse the unfinished acoustic panel, the pics were taken several months ago before I completely finished the room.
up in the attic
manifold trimmed out and inside lined with faux black suede left over from columns, flash from camera washed it out in photo
here's the seating position with no EQ
And the nearfield
I'm pushing the two Ohm speakers bridged to 4 ohms with a Behringer EP1500.
At first it sounded really bad and after measuring i found a huge spike that went from 20 to 40 hz or so. Very odd. My ceiling was uninsulated because my roof is sprayed with foam.
So I added insulation to the ceiling and put a BFD on the system and put some pretty big notch filters in to level it out.
This made a huge difference and at first it sounded great, but after having it for a while and hearing other subs I feel it never really sounded as clean or powerful as my previous DIY 300watt 15" sonotube sub. Perhaps because of all of the electronic correction.
So now I'm thinking of either putting my spare sub on my seating area and taking the mic around the ceiling to see if I can move the IB to a better spot.
Or maybe build a ported box stage for my 18's and place the stage under the screen and forget IB.
here are some pics for room layout and IB install.
IB located just left of room center.

14x 18' long room seats backs at 14-15' from screen. columns have 5" x 6' long slit ripped out of the middle of the sonotube to let some sound through to the insulation inside the columns, not nearly as effective as corner wedges but using my old sub and the ears they did help. Please excuse the unfinished acoustic panel, the pics were taken several months ago before I completely finished the room.


up in the attic

manifold trimmed out and inside lined with faux black suede left over from columns, flash from camera washed it out in photo

here's the seating position with no EQ

And the nearfield
