Peter Jessee
Stunt Coordinator
- Joined
- Sep 25, 2000
- Messages
- 149
I thought that might get your attention.
I've been daydreaming about a possible project and would like some feedback from Those More Knowledgeable Than I (not a real exclusive group....).
I've been trying to come up with a way to 1.) Build a sub with lots of cone area for good "Slam Factor"; 2.) That's capable of high (>115 dBA @ 2 m) output; 3.) That loads the room properly to avoid "peak and dip" issues; and 4.) Doesn't cost a fortune. Here's what I came up with:
Put four 15" Quatro drivers in a 12 cu ft. sealed box – four 15” cones = area of one 30” cone. The box is almost as tall as the ceiling, say 86” x 22” x 12” deep in a typical 90” tall room. The top and bottom drivers are located so that the center of the cones are exactly 1/4 of the room height from the floor and ceiling. The center two drivers are as close together as possible, centered around the half-way point between the floor and ceiling. Place the box at the exact center of the front wall, (assuming a front projector) or the center of a side wall if it would interfere with the video display.
I think a P.E. 500 watt 300-806 plate amp would run this quite well, with the drivers wired series/parallel to make a 4 ohm load, although the 1000 watt 300-808 would still be within the power handling limit for the total driver load. WinISD shows an output of 106 dBA @ 2 meters for ONE driver and 125 watts, so the combined output should be about 12 dB more, or 118 dBA. Add 3 dB for the 1000 watt amp, if desired. F3 is about 36 Hz, perfect for flat installed response of a Q=0.70 sealed box in a typical largish room.
Four 15" Quatro’s are $322.00. The 500 watt amp is $250 right now, allowing $128 to build the box and still be under the $700 mark. Shipping is free until Wednesday.
Has anyone tried a woofer array like this? It sure seems like this would be the next best thing to an IB system, without the holes in the wall. You would get huge air movement with small excursions, keeping distortion low. Depth charges and Death-Star explosions should pin you to the couch.
Comments? Criticisms? Reasons why this won’t work? I’m all ears.
Peter
I've been daydreaming about a possible project and would like some feedback from Those More Knowledgeable Than I (not a real exclusive group....).
I've been trying to come up with a way to 1.) Build a sub with lots of cone area for good "Slam Factor"; 2.) That's capable of high (>115 dBA @ 2 m) output; 3.) That loads the room properly to avoid "peak and dip" issues; and 4.) Doesn't cost a fortune. Here's what I came up with:
Put four 15" Quatro drivers in a 12 cu ft. sealed box – four 15” cones = area of one 30” cone. The box is almost as tall as the ceiling, say 86” x 22” x 12” deep in a typical 90” tall room. The top and bottom drivers are located so that the center of the cones are exactly 1/4 of the room height from the floor and ceiling. The center two drivers are as close together as possible, centered around the half-way point between the floor and ceiling. Place the box at the exact center of the front wall, (assuming a front projector) or the center of a side wall if it would interfere with the video display.
I think a P.E. 500 watt 300-806 plate amp would run this quite well, with the drivers wired series/parallel to make a 4 ohm load, although the 1000 watt 300-808 would still be within the power handling limit for the total driver load. WinISD shows an output of 106 dBA @ 2 meters for ONE driver and 125 watts, so the combined output should be about 12 dB more, or 118 dBA. Add 3 dB for the 1000 watt amp, if desired. F3 is about 36 Hz, perfect for flat installed response of a Q=0.70 sealed box in a typical largish room.
Four 15" Quatro’s are $322.00. The 500 watt amp is $250 right now, allowing $128 to build the box and still be under the $700 mark. Shipping is free until Wednesday.
Has anyone tried a woofer array like this? It sure seems like this would be the next best thing to an IB system, without the holes in the wall. You would get huge air movement with small excursions, keeping distortion low. Depth charges and Death-Star explosions should pin you to the couch.
Comments? Criticisms? Reasons why this won’t work? I’m all ears.
Peter