Hope this isnt a repost.
http://www.digitalgrabber.com/audio/...subwoofer.html
The Biggest Subwoofer Ever Made
Sound Off Legends Richard Clark and David Navone With 60" Sub
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 al 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
The cone moves 6 inches peak to peak under full-tilt output.
The actual cone diameter is 54 inches, with the 3 inch wide surround on the outside of that. The radiating surface area is 2,290 square inches. That yields a one way displacement of 6,871 cubic inches. That is equivalent to the displacement of 161 ten inch woofers that move 1.5 inches peak to peak.
The motor is capable of producing 6,000+ pounds of linear force, which is necessary when considering the very large surface area and displacement volume required to produce high SPL levels.
The woofer was designed with the capability to produce SPL levels of 188 dB, which are entirely possible, given an appropriately built vehicle. It is simply a matter of displacement and containment.
It hasn't seen the light of the car audio industry since 1998 for several reasons. First is money... It isn't cheap to haul it around, and unless it would produce some significant return on investment... You get the idea. Basically, it would be a very high price to pay for some entertainment value and bragging rights.
Also, it would not be legal in competition by current rules because it isn't a typical production, commercially available product.
It is still one of my goals to bring it back out, and let it rip a huge SPL number. Maybe someday, it will prove what it can really do. But for now, only a few people have truly experienced its capabilities. It is outrageously loud, and can make you a sick to your stomach when it plays those very low frequencies.
For those that don't believe it can do what it can do, that's your choice. But, I can tell you that it was designed with strict attention paid to solid engineering principles and practices. Believe it or not, given the right vehicle design, structurally built to withstand the acoustical power of the giant woofer, it could easily produce SPL numbers in the high 180's.
It is one of the coolest things ever created in car audio. It's just too bad no major manufacturers recognize what it could do for their marketing efforts, with a little creative effort.
It's all about achieving the maximum performance in what ever realm you're dealing with, be it sound quality, SPL, road racing, oval track racing, drag racing, motocross, basket weaving, what ever...
The giant subwoofer was created because we thought it would be the most effective way to reach sound pressure levels never before achieved, and we thought it would be a really cool project to design, engineer, and build. The process was like how any vehicle in competitive motor sports are designed and created. You have the rules by which you must play, and you creatively build the fastest car possible within that framework.
Actually, none of the people involved in the design or fabrication of the giant woofer had ever been involved in serious SPL competition. However, each person involved saw the opportunity to push the technology and performance envelopes, and to build something that had never been built before.
Unfortunately, many times if you get too creative, even though you stay within the current rules, they change the rules on you so that your idea becomes illegal. Just ask Hendrick Motorsports about the shocks on Jimmie Johnson and Kyle Busch's cars last year...
Anyhow, the giant woofer was never intended to be anything near a sound quality woofer, nor to be installed in a vehicle that can drive on the street. So don't sweat the idea that it might be responsible for waking you up at night when the neighborhood hoodlums drive by. (More likely, it would implode your windows anyway...)
It was a lot of fun to be involved in building it. It is very effective at getting loud, and at frequencies lower than any other speaker out there. And, if the rules hadn't been changed immediately after the 1997 finals, and an appropriate vehicle could have been built to contain it, the SPL World record would have been set at a mark that still, today, has not been achieved by conventional subwoofer systems.
Someday, it will be back...
http://www.digitalgrabber.com/audio/...subwoofer.html
The Biggest Subwoofer Ever Made
Sound Off Legends Richard Clark and David Navone With 60" Sub
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 al 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
The cone moves 6 inches peak to peak under full-tilt output.
The actual cone diameter is 54 inches, with the 3 inch wide surround on the outside of that. The radiating surface area is 2,290 square inches. That yields a one way displacement of 6,871 cubic inches. That is equivalent to the displacement of 161 ten inch woofers that move 1.5 inches peak to peak.
The motor is capable of producing 6,000+ pounds of linear force, which is necessary when considering the very large surface area and displacement volume required to produce high SPL levels.
The woofer was designed with the capability to produce SPL levels of 188 dB, which are entirely possible, given an appropriately built vehicle. It is simply a matter of displacement and containment.
It hasn't seen the light of the car audio industry since 1998 for several reasons. First is money... It isn't cheap to haul it around, and unless it would produce some significant return on investment... You get the idea. Basically, it would be a very high price to pay for some entertainment value and bragging rights.
Also, it would not be legal in competition by current rules because it isn't a typical production, commercially available product.
It is still one of my goals to bring it back out, and let it rip a huge SPL number. Maybe someday, it will prove what it can really do. But for now, only a few people have truly experienced its capabilities. It is outrageously loud, and can make you a sick to your stomach when it plays those very low frequencies.
For those that don't believe it can do what it can do, that's your choice. But, I can tell you that it was designed with strict attention paid to solid engineering principles and practices. Believe it or not, given the right vehicle design, structurally built to withstand the acoustical power of the giant woofer, it could easily produce SPL numbers in the high 180's.
It is one of the coolest things ever created in car audio. It's just too bad no major manufacturers recognize what it could do for their marketing efforts, with a little creative effort.
It's all about achieving the maximum performance in what ever realm you're dealing with, be it sound quality, SPL, road racing, oval track racing, drag racing, motocross, basket weaving, what ever...
The giant subwoofer was created because we thought it would be the most effective way to reach sound pressure levels never before achieved, and we thought it would be a really cool project to design, engineer, and build. The process was like how any vehicle in competitive motor sports are designed and created. You have the rules by which you must play, and you creatively build the fastest car possible within that framework.
Actually, none of the people involved in the design or fabrication of the giant woofer had ever been involved in serious SPL competition. However, each person involved saw the opportunity to push the technology and performance envelopes, and to build something that had never been built before.
Unfortunately, many times if you get too creative, even though you stay within the current rules, they change the rules on you so that your idea becomes illegal. Just ask Hendrick Motorsports about the shocks on Jimmie Johnson and Kyle Busch's cars last year...
Anyhow, the giant woofer was never intended to be anything near a sound quality woofer, nor to be installed in a vehicle that can drive on the street. So don't sweat the idea that it might be responsible for waking you up at night when the neighborhood hoodlums drive by. (More likely, it would implode your windows anyway...)
It was a lot of fun to be involved in building it. It is very effective at getting loud, and at frequencies lower than any other speaker out there. And, if the rules hadn't been changed immediately after the 1997 finals, and an appropriate vehicle could have been built to contain it, the SPL World record would have been set at a mark that still, today, has not been achieved by conventional subwoofer systems.
Someday, it will be back...
Comment