HELP! I am finishing my basement, and plan to build a home theater with a subterranean cave theme. I have attached a jpeg image of the proposed floorplan of “THE CAVE,” and am looking for critics, suggestions, acoustical advice, etc. I am an amateur, but this is what I have planned: There will be no 90 degree corners in the room. The dimensions will be as follows: Approximately 18 feet from side to side Approximately 20 feet from front to back Ceiling height 9 feet (with domed fiber optic starfield) ENTRANCE: The soundproof door will be a heavy 3” thick, 4 ft diameter round Bilbo-Baggins style door (as seen in Lord of the Rings). As you come in the tunnel-like entrance you will walk up a ramp to an elevation about 2 feet off the concrete floor. The ceiling of the tunnel will have a rounded barrel vault, and there will be medieval sconces with torch-like lightbulbs recessed into the walls of the passageway. THEATER: At the end of the tunnel you walk into the theater. Remember, you are standing 2 feet off the concrete floor, and as you look toward the front you will notice that there are four rows of eight seats, with each row on its own level, and a 6” drop between each level as you go towards the front. AISLE: The center aisle between the seats will not have steps, but rather be a sloped ramp leading down to grade level. WALLS: Other than a 10 ft wide section where the fixed screen will be positioned, none of the walls will be totally flat. After framing the rounded wall sections with rounded corners, I will attach thin strips of plywood horizontally to the studs for screwing the wallboard to. I will then attach 3/8” sheetrock throughout the room, bending it as necessary to conform to the walls. Following is one of my big questions: From an acoustical standpoint, would it make sense to cover the sheetrock with acoustical ceiling tiles? I just salvaged hundreds of 2’x4’ ceiling tiles (as well as 35 plush, high-backed theater seats) from a local cinema which is being torn down. My plan is to screw the ceiling tiles to the wallboard in random patterns, sometimes with two or three thicknesses to create a contour like you would see in a cave. I will bevel the leading edges, and before painting I will use caulking or drywall mud to cover any screw holes and hide any joints. I will use some kind of flat black or dark gray acoustical paint (any suggestions?) on the walls. CEILING: Near the top of the walls (at about the 7 ½ ft level) I will transition to the ceiling with a dropped soffit (with coved corners) that will extend about 4 feet toward the center of the room on the sides and the back wall. The soffits will then end, and there will be 6” vertical transition to a domed ceiling with a 9 ft height at the center. I plan to construct a fiber optic starfield complete with comets and shooting stars. AUDIO/VIDEO: Will purchase either DENON or SONY equipment, with all equipment in a rack at the back behind a hidden door. Will use IR repeaters for remote operation. All speakers including subwoofer will be recessed into walls, and covered with acoustically transparent screens. (Is there an acoustically transparent paint or dye that I could use to match my wall paint so the speakers will disappear?) I will use a projector which I will mount on the ledge in the rear soffit, projecting about 18 feet to the fixed screen. FINAL DETAILS: I will paint some veins of reflective silver and gold in the walls, and maybe some caveman-style stick figure art. A life-sized T. Rex fossil jutting out of the wall (idea from a Monster House episode) would add a nice dimension, and I may also build some Styrofoam stalactites and/or stalagmites, painted to look like the real thing. Some rubber Halloween bats with blinking LED eyes would be right at home hanging from the soffited ceiling. In conclusion, I am not married to any of my ideas. I’ve just been thinking about this for a long time, and when I built my house last summer I purposely framed in a large square room in a corner of the basement on the opposite end of the house from the bedrooms. My wife thinks its going to be a storage room………heh heh heh!