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Okay, I have a question for all you port guys out there........just FYI, I'm going to run a pair of oz audio 250L (10"s) for sq in a ported box in the back of my camaro. They will be facing eachother at 45* angles, like this \_/ with the single 4" aeroport in the middle(where the underscore_is)......My question is, I'd like to have a fairly even response from the subs......This is what I would like to do....make a temp. sealed box and use a radioshack spl meter and a test cd to find my car's note. then measure the notes before and after it, graph it and hopefully be able to determine the in-car response slope.....Then build a ported box to the specs I'm going to use and measure the response slope of that box (Where's a good place to measure this? (in my house?, outside?, should I just make sure there is nothing to reflect the wave back?) and graph that as well. compare the two graphs and lower the tuning frequency of the box untill the two slopes cross over evenly......Does this sound like something feasable? or am I going to waste my time???
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also, i've read on this forum that the spl guys will tune 10hz below the freqency of their car. Why is this?? and how should I take that into consideration?
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A good way to measure the out of car response is to do it outside. You will want to raise the sub off of the ground a little to be more accurate, and have the meter at the same height as the sub.
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as an spl guy i'll let you know that we tune usually 1-3hz below the resonant frequency...not 10. about what you wanted to know.....i haven't a clue.
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Your wanting to do all this for SQ? Sounds kinda like your really after SPL. Are you trying to decide between the 2 box styles?? Building one for each is a good idea! For SQ, you need to build a couple of different sized boxes, stick them in your car and give it a good listen, then let your ears decide. The Oz 250L's have always worked best for me in a 1.48cf3 box Sealed and stuffed with 1.5 lb of polyfill.
------------------ STILL waiting to hear a GOOD pair of HLCD's!!
If it dont fit, force it... if it breaks, it needed to be replaced anyway...
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well, actually, my goal was to utilize the 3-6db increase from porting by tuning it to the frequency band where the in-car 12db(estimate)rolls off to get an even curve that will be louder throughout the lower three octaves.......its just a thought, I just wanted to see what you guys thought......And thanks Audiophyle, I'm gonna make a couple different boxes....and definatly try those telarc 1812 cannon shots. =)
------------------ Alpine PG PPI Tube Driver Oz Audio Phaze Audio = The tools of my obsession...
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I personally think you'd be doing yourself a disservice by using those woofers in a ported box, I personally think they sound much better sealed.
------------------ STILL waiting to hear a GOOD pair of HLCD's!!
If it dont fit, force it... if it breaks, it needed to be replaced anyway...
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