What is the loudest records holding subwoofer\subwoofers in size.

[Flipx99 5,000+ posts]

Breaking/Folding cones isn't the only issue. Keeping the coil under control is a huge part of it to. and when the cone is being forced in wierd driections it causes the coil to rock in the gap.
I wish I could find my cameral...i have a folded MT cone here at the house I coudl show...but no camera //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

I often thought about that...even in non-spl applications where the cone is horizontal, it would seem like that would be more apt to happen. I would think the magnet field around the motor would keep it somewhat aligned during normal applications. At higher pressures, I could see how minor deflections in the cone would cause the coil to wobble or rock in the gap.

I assume someone is working on proposed solutions...My knowlegde of electromagnetic dynamics is quite limited where I could not think of a way (electronically) to keep the coil perfectly centered in the gap in extreme situations. I would assume driver orientation plays a part but to what extent, I do not know. Furthermore, it would seem that driver orientation plays a key role in achieveing a higher SPL. Perhaps any gains that driver orientation could provide is eroded by loss of SPL.

Sorry if this seems like rambling. Just want to be sure if what I am thinking is atleast somewhat correct.

 

[Chevyaudio 5,000+ posts]

there is much more than just building a concrete shell and throwing speakers in it.

The designs are very intricate. I mean look at Dante and the enclosure he is using...an adaptation of an 8th order bandpass. You could line a van with concrete and steel replace the glass with plexi, and throw a few ported boxes in there, and be no where near where they are at. Acoustical design is a HUGE portion of the extreme class.

 

[Flipx99 5,000+ posts]

We need more threads with info this good //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif
But yeah that makes a lot of sense. I think the "extreme" vehicles are ridiculous, and yeah they look like armored troop carriers more than actual cars/trucks. I mean, the smaller and sturdier the space you are trying to pressurize with sound the less displacement it takes. To me, it crosses over from "car audio" to something else when you basically just have a thick metal box and the goal is to have as little air space as possible inside it. When you get to that point, why not just have a "metal box audio" competition, and just have people wheel up pressurized metal globes and throw a sensor in there to see how loud it gets.

They make rules to prevent this. Remeber, it is car audio and people are pushing the limits of what is and isn't car audio.

It's not concrete box on wheels audio.

IMO, I think TommyK hitting 15x.x off 1 10 is more impressive than others doing 16x.x with many more woofers and amps. But that is why they make different classes.

 

[Flipx99 5,000+ posts]

there is much more than just building a concrete shell and throwing speakers in it.
The designs are very intricate. I mean look at Dante and the enclosure he is using...an adaptation of an 8th order bandpass. You could line a van with concrete and steel replace the glass with plexi, and throw a few ported boxes in there, and be no where near where they are at. Acoustical design is a HUGE portion of the extreme class.

But I never see any of the competitors holding advanced degrees in physics, mechanical engineering, etc. It seems like there is a better way to model besides build and test, build and test.

 

[Chevyaudio 5,000+ posts]

I often thought about that...even in non-spl applications where the cone is horizontal, it would seem like that would be more apt to happen. I would think the magnet field around the motor would keep it somewhat aligned during normal applications. At higher pressures, I could see how minor deflections in the cone would cause the coil to wobble or rock in the gap.
I assume someone is working on proposed solutions...My knowlegde of electromagnetic dynamics is quite limited where I could not think of a way (electronically) to keep the coil perfectly centered in the gap in extreme situations. I would assume driver orientation plays a part but to what extent, I do not know. Furthermore, it would seem that driver orientation plays a key role in achieveing a higher SPL. Perhaps any gains that driver orientation could provide is eroded by loss of SPL.

Sorry if this seems like rambling. Just want to be sure if what I am thinking is atleast somewhat correct.

yes, you are on the right track.

driver orientation in certain aplications can help this problem...mainly through loading. Take my unique situation for example.

I compete in a single cab truck...with the driver forward firing (towards the seat) the sub does all kinds of funky things when I start put some power to it...mainly because of the proximity to that seat that is in front of it...even though the seat is a foot or more away it still affects the way the driver "loads".

When I upfire the sub in the same box I gain a few 10ths and sub is fine.

 

[Chevyaudio 5,000+ posts]

They make rules to prevent this. Remeber, it is car audio and people are pushing the limits of what is and isn't car audio.
It's not concrete box on wheels audio.

IMO, I think TommyK hitting 15x.x off 1 10 is more impressive than others doing 16x.x with many more woofers and amps. But that is why they make different classes.

But Tommy is gay fairy? //content.invisioncic.com/y282845/emoticons/wow.gif.23d729408e9177caa2a0ed6a2ba6588e.gif

 

[Buffalohed 10+ year member]

On the subject of coil alignment, I bet some kind of very dense non-reactive fluid suspension would help. Of course, that would be expensive as ****, hard to design, and a hell of a lot more complicated than your average SPL woofer. It would be cool as **** though.

I'm not sure exactly how subwoofers work but another idea would be a magnetic field perpendicular to that of the coil, with a functional radius small enough to keep the coil away from the gap. Kind of like how particles in a super collider are kept in the center of the accelerator.

 

[Chevyaudio 5,000+ posts]

But I never see any of the competitors holding advanced degrees in physics, mechanical engineering, etc. It seems like there is a better way to model besides build and test, build and test.

But then you run into "what works on paper wont work in the real world" situations.

99% of this sport is experience.

 

[Jeremiah25 10+ year member]

But I never see any of the competitors holding advanced degrees in physics, mechanical engineering, etc. It seems like there is a better way to model besides build and test, build and test.

That's because you don't know much about the competitors. I already have a minor in mathematics, and physics and am working on a double major in Mechanical Engineering and Industrial Management. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[Chevyaudio 5,000+ posts]

That's because you don't know much about the competitors. I already have a minor in mathematics, and physics and am working on a double major in Mechanical Engineering and Industrial Management. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif...

Contrary to popular belief this sport is not entirly comprised of rednecks in the back yard with a table saw and a few Lawn Mower batteries (even though those guys do exist), lol

Also kinda off topic...Jeremiah are you going to Streetbeat again this year is USACi.

 

[Flipx99 5,000+ posts]

On the subject of coil alignment, I bet some kind of very dense non-reactive fluid suspension would help. Of course, that would be expensive as ****, hard to design, and a hell of a lot more complicated than your average SPL woofer. It would be cool as **** though.
I'm not sure exactly how subwoofers work but another idea would be a magnetic field perpendicular to that of the coil, with a functional radius small enough to keep the coil away from the gap. Kind of like how particles in a super collider are kept in the center of the accelerator.

Yes, there is something that would work. It's called MR fluid. They use it in buildings as an isolator for earthquakes. It is essential an electromagnet attaches to a solenoid so it turns an electromagnetic field on and off very very fast to cushion the building. I have no idea how one would adapt this technology to a subwoofer though.

The problem is, you would have to have a magnet of such great strenth to keep the coil perfectly centered. An electromagnet would be better at this application, but then the subwoofer becomes more mechanical and less "musical" if you will.

 

[Flipx99 5,000+ posts]

That's because you don't know much about the competitors. I already have a minor in mathematics, and physics and am working on a double major in Mechanical Engineering and Industrial Management. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

I was hoping an inflammatory comment would get people to tell me what I didn't know. I wasn't trying to offend, but illicit a response.

 

[Buffalohed 10+ year member]

I think musicality is out of the picture far before we start talking about synthetic fluid suspensions for SPL woofers //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

Anyway, the magnet wouldn't need to be very strong. Magnetic field strength is inversely proportional to distance from the center of the field, which is why I said it would have to the field would have to have a small radius, near the coil.

 

[Flipx99 5,000+ posts]

I think musicality is out of the picture far before we start talking about synthetic fluid suspensions for SPL woofers //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif
Anyway, the magnet wouldn't need to be very strong. Magnetic field strength is inversely proportional to distance from the center of the field, which is why I said it would have to the field would have to have a small radius, near the coil.

But you can move it under pressure. Kind of like how you can force two small magnets together in your hands. We got some 50lb electromagnets at work that I can stand on and it won't touch the other magnet. (However, it moves real quickly out from under you)

 

[Jeremiah25 10+ year member]

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif...

Also kinda off topic...Jeremiah are you going to Streetbeat again this year is USACi.

Yes and no. I am going to run at Steve's 300th, but it will probably be my last show. I don't think I will be going to finals.

The only reason that would change is if something goes wrong with my run at Steve's 300th, and I don't get to do my score.