------------------ Team "Under Pressure"--coming soon to SE Minnesota for a summer tour wall w/three shocker15's and a cadence a7hc...in a tiny corolla
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Of course all of us could build vehicles with interior cabins shaped like hollow spheres, maybe we would see some gains. But isn't the fun part of life figuring out how to get around the laws of our universe instead of working with them.
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Posts: 68 | From: Port Angeles, WA, United States | Registered: Apr 2001
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My guess on why baffles work is that rather than the kinetic energy within the box being concentrated in one area where there is high airflow it will be spread about, but the energy density will be lower, so less energy used up moving the air about.
We don't accept dead air in out boxes
Dank, not sure what you meant by capacitive ports and inductive sealed boxes???
Colin
------------------ Spy Shots Warning SPL in my car exceeds government health guidelines, civilians are advised to proceed with caution. Failiure to comply may result in serious injury or death.
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If you model a ported box as the equivalent electrical circuit the port is modeled as a capacitor and small resistor. I still dont know how to get all the values in the equivalent circuit.
------------------ 2-DD 9512's 2-2000X's (for now) 8.0ft^3 box in a civic trunk One big ass port ?????dB's
It's not the size of your woofer, It's the size of the waves your woofer makes!
Posts: 1259 | From: Fullerton. CA ,USA | Registered: Oct 1999
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i don't think SPL numbers would change by much if you round the corners. I am not an engineer, but I think I figured out how they got such high numbers with two 15s. Well, besides the fact that they had 10,000 watts or so, I believe that the inside of their cabin is almost like the inside of a port. I think that the backwave that is produced by the subwoofer is actually in-phase with the front wave that is produced by the subwoofer, and they used just the right vehicle/frequency/tube combination to get it just right. What that I mean is that when the front sound wave reflects off the firewall, when it reaches the rear of the vehicle it is in-phase with the rear sound wave that went through the "tube" after it was produced when the sub's cone moved in. eh, hmmm. on a different note, maybe when he pluged in numbers into a port design software program, he calculated the enclosure volume as the volume inside the cab of the vehicle. Then the port surface area will be the cross-sectional area of the inside of the cabin, minus the surface area that the enclosure's face takes up. Then the only thing left will be port length, so you build the tube to the required "port length". But if this was the case, then I would imagine there would be phase issues after reflections, so maybe i'll stick with what i said at first. damn, i'm bored as hell at work only an hour left for fux sake!
------------------ *24/7 man! QoTSA Better Living Through Chemistry
Posts: 141 | From: lala land | Registered: May 2001
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