Might be a repost, anyway.
The 60-inch subwoofer absolutely has the capability to produce SPL levels well above 180 dB. It is simple math and the laws of physics.
Actually, before designing it, we looked at a comparison between a large number of conventional subwoofers, or a single giant one. After we did the math, the obvious choice was the one giant woofer. It's output displacement is comparable to 160+ ten inch woofers. It can move a lot of air!
The original idea for the giant subwoofer came about in 1994 when Doug Winker, Chris Lewis, and myself were investigating how to create the highest SPL levels, just for fun. The giant sub was the best performance option, but we didn't have the capability or finances to build it at the time. Anyway, that year was when Chris and Doug installed the dual compression drivers with the horn mouth right below the mic location against the windshield. Unfortunately, the horn system was "disqualified" by the head SPL judge because the rules said the competitor could not have any windows cracked open, and Chris' windshield was cracked. I guess it didn't make any difference that the rule was intended to ensure all the windows were rolled up, and there were no openings to the outside that could affect the SPL reading.
Anyway, the 60-inch sub came about in 1997 while I was working with RC and Dave in North Carolina. Tim Maynor wanted to build a new SPL vehicle, and wanted Autosound 2000's help. We looked at the different possibilities for woofer configurations, and with Dr. Eugene Patronis' help (from Georgia Tech), we designed and built the giant subwoofer in about a six week period.
Unfortunately, Tim and his crew didn't realize just how much acoustical power the sub could generate, and didn't build the vehicle to contain it appropriately. Even at less than 1/2 output, the doors were blown off the tracks, and the entire vehicle ballooned in and out several inches. The woofer was installed in the "bread truck" anyway, and it went to Finals not fully tested.
At the Finals in 1997, Alma protested the use of the computer used to control the energy fed to the subwoofer by the power supply, so RC had to try to do it by simply touching two cables together with no feedback, and hope that the energy level was correct when it was set off. As it turned out, it wasn't at the right level, and the speaker's motor simply drove the cone assembly too hard and too fast, and snapped part of the main conecting tube in half. But, it did do 162+ dB with a single positive stroke of the cone before it broke!
The woofer was updated with several modifications after that incident so that it won't have problems with breaking again.
More.
The 60-inch subwoofer absolutely has the capability to produce SPL levels well above 180 dB. It is simple math and the laws of physics.
Actually, before designing it, we looked at a comparison between a large number of conventional subwoofers, or a single giant one. After we did the math, the obvious choice was the one giant woofer. It's output displacement is comparable to 160+ ten inch woofers. It can move a lot of air!
The original idea for the giant subwoofer came about in 1994 when Doug Winker, Chris Lewis, and myself were investigating how to create the highest SPL levels, just for fun. The giant sub was the best performance option, but we didn't have the capability or finances to build it at the time. Anyway, that year was when Chris and Doug installed the dual compression drivers with the horn mouth right below the mic location against the windshield. Unfortunately, the horn system was "disqualified" by the head SPL judge because the rules said the competitor could not have any windows cracked open, and Chris' windshield was cracked. I guess it didn't make any difference that the rule was intended to ensure all the windows were rolled up, and there were no openings to the outside that could affect the SPL reading.
Anyway, the 60-inch sub came about in 1997 while I was working with RC and Dave in North Carolina. Tim Maynor wanted to build a new SPL vehicle, and wanted Autosound 2000's help. We looked at the different possibilities for woofer configurations, and with Dr. Eugene Patronis' help (from Georgia Tech), we designed and built the giant subwoofer in about a six week period.
Unfortunately, Tim and his crew didn't realize just how much acoustical power the sub could generate, and didn't build the vehicle to contain it appropriately. Even at less than 1/2 output, the doors were blown off the tracks, and the entire vehicle ballooned in and out several inches. The woofer was installed in the "bread truck" anyway, and it went to Finals not fully tested.
At the Finals in 1997, Alma protested the use of the computer used to control the energy fed to the subwoofer by the power supply, so RC had to try to do it by simply touching two cables together with no feedback, and hope that the energy level was correct when it was set off. As it turned out, it wasn't at the right level, and the speaker's motor simply drove the cone assembly too hard and too fast, and snapped part of the main conecting tube in half. But, it did do 162+ dB with a single positive stroke of the cone before it broke!
The woofer was updated with several modifications after that incident so that it won't have problems with breaking again.
More.
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