kryptonitewhite Posted February 21, 2009 Author Report Share Posted February 21, 2009 (edited) build a t-line.... tune it to 11Hz, that way, an octave up or doun and you will be happy. you could play 1 cycle or 21. Is that low enough? I think you are pushing it just a bit. butt dud i wish you the best in your trials. how about I do that but bump it up to 22Hz though, then i am at the drivers Fs as well EDIT: only 13 feet 1/4 wavelength, I could pull that off Edit Edit: isn't 1 octave below 11Hz 5.5Hz? Edited February 21, 2009 by kryptonitewhite Quote IB3 22" Link to comment Share on other sites More sharing options...
kryptonitewhite Posted February 21, 2009 Author Report Share Posted February 21, 2009 (edited) I thought I was tuned to 14Hz in 22 cubes to begin with but I was at 16Hz with 20 cubes. I cut my 20" port down to 10 so i am at 21 cubes @ 20Hz now. Later I'll cut it down to 5" for a 25Hz tune. I hope I make a decision I'm happy with, then I can make the new box for the 22". FR curve 16Hz 20.5 cubes vs 20Hz 20.8 cubes vs 25Hz 21 cubes nice thing about tuning below your desired range is ports are bad. group delay, turbulence, port compression, resonance... if you tune below where you center your play, yes you will lose SPL, yes you will have more excursion, but you will have less undesired effects as well not making the port do all the work. no matter the driver, no matter the Fs, power handling, 1 super loose spider or 5 super stiff, super high BL with huge magnets or low BL with tiny magnets and top/bottom plate.... when you tune lower then you will have a hump up higher where power handling is down, excursion is up, and SPL is down. When tuning below 30Hz you will have an issue from 30-50Hz, you can see it clearly here from 18Hz-43Hz on the low tuned and 29Hz-43Hz on the higher tuned same goes for SPL IDK what the difference is between the "transfer function magnatude" and the "SPL" graph, both look like FR curves to me the most important to me... power handling is generally more a mechanical problem than a thermal one if you have good clean power. It's mostly about bottoming out and clipping I feel. xcursion resistance wind: I make a lot of it now that i shortened my port! I got hit in the eyes twice with sawdust I couldnt get vaccumed out.. saw it blow from inside the port strait at me up front... a good 4 feet! It BLOWS! We can feel port wind up front, but can't hear it. With the lower tune, we had very low excitation, little port velocity... and people were afraid 7.75" was too small. The lower you tune, I believe even more strongly now than before that port area requirement is lessened. A cone moving full excursion at 30Hz tuned to 30Hz moves a lot more air (twice as fast) as the same cone full excursion at 15Hz tuned to 15Hz. of course as you lower tuning below your goal, not only do you lose the negative side effects, you lose your gain as well Edited February 21, 2009 by kryptonitewhite Quote IB3 22" Link to comment Share on other sites More sharing options...
Team_DC-Derrick Posted February 21, 2009 Report Share Posted February 21, 2009 http://www.stevemeadedesigns.com/board/ind...&hl=sleeper Quote The DC Integra 3 18s to 6 15 build log Team_DC-Derrick's Youtube Team DC Audio where theres a will theres a wall....... I just realized Steve has reach Voldemort status, over on JP's site he is the one who will not be named....."We dont speak his name over here, fearing it will destroy us" LOL not even in hush tones Link to comment Share on other sites More sharing options...
07sOnAtA sp.ed Posted February 21, 2009 Report Share Posted February 21, 2009 i wish i could help, but im not 100% sure i understand what your asking... Quote CURRENTLY UNDER RE-CONSTRUCTION 2008 Hyundai Sonata Team T3 Audio Team Deadly Hertz Team SMD (Street Motivated Devastation) Link to comment Share on other sites More sharing options...
kryptonitewhite Posted February 21, 2009 Author Report Share Posted February 21, 2009 http://www.stevemeadedesigns.com/board/ind...&hl=sleeper Oh yes I saw this on ROE a week ago, 6th order/horn... I think I saw something about how it kind of blends between the two? SICK. That would be fun... but I don't think that qualifies as a dirt floor poor... Quote IB3 22" Link to comment Share on other sites More sharing options...
kryptonitewhite Posted February 21, 2009 Author Report Share Posted February 21, 2009 i wish i could help, but im not 100% sure i understand what your asking... Not really asking anymore for now, ya'll talked me into cut some port.. and I did, and I'll do more soon. I wanted to plot a little too for a bit of insight, though it doesn't mean much in-car. But when ya see somethin, spit it out Quote IB3 22" Link to comment Share on other sites More sharing options...
kryptonitewhite Posted February 22, 2009 Author Report Share Posted February 22, 2009 (edited) cut the port from 10" to 4.75" went from 20Hz to 25Hz. Over all it s a little louder, but the low low songs the low parts all but disappeared. Bass I love you blows SERIOUS air way up front, gotta get some vids with the good camera. (edit: but you cant hear/feel the 18Hz tone at all the same way as before) Bottoming is not an issue now when songs change and we go from sub 27Hz tracks to songs from 27Hz-35Hz with the doors shut. Bass I love you just about hits bottom with the doors open, but I won't be driving with them open! I think I like the 15Hz the best, 20Hz second, and 25Hz the least.... I didn't expect that, I thought it would get much louder with a lot less excursion tuning higher, but thats actually not what I'm seeing overall... but that varys so much from song to song. the longer 10" from yesterday and the 5" from today Edited February 22, 2009 by kryptonitewhite Quote IB3 22" Link to comment Share on other sites More sharing options...
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