pervitizm Posted April 15, 2010 Report Share Posted April 15, 2010 I'm trying to follow the sticky write up on building Quarter Wave enclosures. I've finally gotten the nerves to try one out on a 12 in elemental design sub that I've had sitting around for years now. I did the math on the sub and I came up with these numbers: T-Line (eD 13Kv.2) To calculate length of Freq divide 1130 / (Fs freq) = Full wave Length To calculate Quarter Wave length divide (Full Wave Length / 4) Take the SD (cone area) if in cm2 (squared centimeters) convert to in2 (squared inches) 1.) 1130 / 21.5Hz = 52.55 ft – rounded to 53 ft 2.) 53 ft / 4 = 13.25 ft Q-wave length 3.) SD =545cm2 which is 84.48in2. The line has to be 84in2 So based off of what I have, I'll need a line that is around 13 feet long with a port area of around 84sq inches, does this sound right to you? Here are the specs based off of that 13Kv.2 sub that want to use: Qts: .31 Qes: .35 Qms: 3.33 Fs: 21.50Hz Re: 3.7 Vas: 162L Mms: 142.0g Bl: 15.00T*m SPL: 88.47dB Sd: 545cm² Xmax: 15.1mm Voice Coil: 50.0mm Magnet Width: 5.700" Cutout Diameter: 11.000" Mounting Depth: 5.750" Weight: 14lb Total Height: 6.250" Displacement: .06 ft³ Outside Diameter: 12.375" I'll want to try and sketchup a design later on this evening when I get home from work. The two main issues that I have when designing one of these is how do you calculate the fold when doing a folded design, and how do you deal with woofer displacement when your woofer displacement is actually bigger than you line? What I mean is this, say my line has a depth of around 8 inches from the front baffle to the line wall, but I need a mounting depth of 8.5 inches for my woofer to fit. How do you deal with getting that extra .5 inches? Doing an inverted install wouldn't work out to well for my enclosure's final location. Sorry for such a long post but I think I'm on the right path with this I'm just looking for a bit more guidance. And I know if I can figure this out for a 12 then when I'm ready to try it on one of my 18's the design phase will be much much easier. Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
liftedranger08 Posted April 15, 2010 Report Share Posted April 15, 2010 That looks to be correct. Now for your sub to fit, you could do a a spcaer under the sub. I would say do a 3/4" spacer. That should raise the sub up enough so it wont hit the inside of the box. Quote 2000 White Ford Ranger 5" RCD lift 33x12.50 Mickey Thompson MTZs on 16x8 Mickey Thompson Classic 2s Euro Altezza tail lights 5% window tint Clarion Indash 4 Q Power 15s 1 Sundown 2000 1 DC power 300 amp alt(on the way)-soon to be 2 2 powermaster d925s batteries Second Skin Deadener Highs/mids amp-Crossfire 404 Door speakers-2 5x7 mb quarts and 1 5 1/4" black max up front, stock 5x7s in the rear Soon to Come: Lots of SA-8s 2 Sundown saz 3500s(possible 4500s) 5-7 d3100 batteries custom clamshell BNC 8s for mids undecided tweeters Link to comment Share on other sites More sharing options...
kandiman71874 Posted April 15, 2010 Report Share Posted April 15, 2010 (edited) That looks to be correct. Now for your sub to fit, you could do a a spcaer under the sub. I would say do a 3/4" spacer. That should raise the sub up enough so it wont hit the inside of the box. Spacer is the correct idea, but yer only leaving a 1/4" behind the motor doing a single layer of 3/4" mdf. If the sub has a pole vent of any kind I would at least do 1.5 inch spacer to let the motor assembly breathe a little for cooling purposes. Next thing to address here though is what/where will you be putting this enclosure once it is built. A 1/4 wave with a line length of 159 inches tuned to the FS of that sub is going to be huge... Edited April 15, 2010 by kandiman71874 Quote Daily Driver 1999 Kia Sephia Kenwood DNX-893s Audison Bit One Processor 2 Dat 4.125's Sundown Audio SCV-6k Hertz hsk-165xl's Mids running active Focal V30 Series Tweeters running active Sundown Sa-8 v1's in the doors 2 Sundown Zv5 12's Lots of Hushmat Big 3+ and 3 + & 3- runs of Trystar 2/0 2 Dc Power Engineering 320 HP Alts 2017 Comp Vehicle 2006 Toyota 4 Runner Kenwood Excelon DNX-893s Audison Bit One HD DSP 4 Sundown Sa 6.5v2 Component Sets Focal Access 6.5 2 ways Sundown Audio Sax-50.4 Sundown Audio Sax-100.4 2 Dc Power 370xp Northstar agm27f Northstar agm65 2 Northstar asmagm 480's 2 Dual 1 Sundown Nightshade v3 12's 2 Sundown SCV-7500's All SMD Fuse Holders Shitload Of Sundown 1/0 120 sq ft Second Skin Damp Pro No, Its Not A Burp Truck!!!! 2016 Season 3rd place in Xtreme 1 At Finals 2016 Season 6th Place In Kaos 1 At Finals ( Blew The Subs Up In First Round Eliminations) 2 Kansas State Records Set In 2016 In Xtreme 1 And Kaos 1 In Midwest SPL David said: audio is a lifestyle, not a hobby newls1 I cant read a tape to save my life... 1/2's are ok, but other marks confuse me kingsuv only men who cant read a tape, take it in the ass kingsuv you sir, get a pink hard hat on jobsites Link to comment Share on other sites More sharing options...
pervitizm Posted April 16, 2010 Author Report Share Posted April 16, 2010 Spacer is the correct idea, but yer only leaving a 1/4" behind the motor doing a single layer of 3/4" mdf. If the sub has a pole vent of any kind I would at least do 1.5 inch spacer to let the motor assembly breathe a little for cooling purposes. Next thing to address here though is what/where will you be putting this enclosure once it is built. A 1/4 wave with a line length of 159 inches tuned to the FS of that sub is going to be huge... This would go either in the living room or the wife's van. So when you guys build these you do the line by the inches instead of by the foot? Is it easier to do the line by inches? And the spacer ideal is good. I kinda thought that would be the way to go. I'm about to do a quick sketup of what I think this should look like. Hopefully some of you guys in here can take a look and let me know if I'm on the right path with this. Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
pervitizm Posted April 17, 2010 Author Report Share Posted April 17, 2010 Ok so I sketched up a drawing in google's sketchup. Now I didn't add the top to this but the box height with the top on is only 12inches high. So if HxWxD then the box is 12 x 45 1/2 x 27 3/4. The three drawings are of the same box just showing different measurments for what I wanted to illistrate. Now to get my 84sq of line I did a HxW of 10.5 x 8 = 84sq. So the lines wide is 8 inches high by 10 1/2 height. This image here shows how I kept the line a constant 8 inches wide throughtout the line including in the folds with the 45's there. This next image shows the box outer dimentions along with the 45's as well. The only dim I didn't show what the height, and that was because I didn't draw the top of the box. This last image is the one I have the queston on. When I did the finial go throught on this box I come out with a final line lenght of only 115 inches or roughtly 9 1/2 ft. Without the 45's I have a box that is 175 inches or 14ft. Why did my 45's take away almost 4ft of area? The only way I could add 45's and keep the line constant thoughtout the folds was to add those size 45's. Can I build the line without the 45's? Would I notice the difference? Or better yet did I calculate the line measurment in this last pic correctly? Any help and feedback I can get will be greatly appreciated. Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
kandiman71874 Posted April 17, 2010 Report Share Posted April 17, 2010 Line length is measured down the center of the tunnel for length. average person looking at that is gonna miss the additonal 4 inches on each fold Quote Daily Driver 1999 Kia Sephia Kenwood DNX-893s Audison Bit One Processor 2 Dat 4.125's Sundown Audio SCV-6k Hertz hsk-165xl's Mids running active Focal V30 Series Tweeters running active Sundown Sa-8 v1's in the doors 2 Sundown Zv5 12's Lots of Hushmat Big 3+ and 3 + & 3- runs of Trystar 2/0 2 Dc Power Engineering 320 HP Alts 2017 Comp Vehicle 2006 Toyota 4 Runner Kenwood Excelon DNX-893s Audison Bit One HD DSP 4 Sundown Sa 6.5v2 Component Sets Focal Access 6.5 2 ways Sundown Audio Sax-50.4 Sundown Audio Sax-100.4 2 Dc Power 370xp Northstar agm27f Northstar agm65 2 Northstar asmagm 480's 2 Dual 1 Sundown Nightshade v3 12's 2 Sundown SCV-7500's All SMD Fuse Holders Shitload Of Sundown 1/0 120 sq ft Second Skin Damp Pro No, Its Not A Burp Truck!!!! 2016 Season 3rd place in Xtreme 1 At Finals 2016 Season 6th Place In Kaos 1 At Finals ( Blew The Subs Up In First Round Eliminations) 2 Kansas State Records Set In 2016 In Xtreme 1 And Kaos 1 In Midwest SPL David said: audio is a lifestyle, not a hobby newls1 I cant read a tape to save my life... 1/2's are ok, but other marks confuse me kingsuv only men who cant read a tape, take it in the ass kingsuv you sir, get a pink hard hat on jobsites Link to comment Share on other sites More sharing options...
pervitizm Posted April 17, 2010 Author Report Share Posted April 17, 2010 I'm not sure I'm following what your saying. What 4 inches are you referring to? Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
pervitizm Posted April 17, 2010 Author Report Share Posted April 17, 2010 Okay so I played around with it again. This time I think I got the line count right, the bad though is that I'm still around 2ft short of my 13ft line. Take a look below. The first pic shows the cross section lines of the middle of the line. Again my line is 8 inches wide so the middle of the line is 4 inches. So after taking another look at the sticky I decided to remeasure my line again based off what I read somewhere around page 12 of the sticky. So this is what I came up with 31 1/4 + 27 1/4 + 36 +8 3/4 + 8 3/4 + 22 7/8 = roughly 135inches. Again I'm still not there yet but I think I'm getting closer. This is just a cleaner picture without the cross section lines, which makes it easier to see. Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
STEvil Posted April 18, 2010 Report Share Posted April 18, 2010 using 1/2 circle radius would give you a more correct number for the corners. Flare the mouth if possible, free horn area! Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
pervitizm Posted April 18, 2010 Author Report Share Posted April 18, 2010 Thanks for the suggestion. Quote 2007 Chevy Suburban LT1 Pioneer AVH 5700 DVD Diamond Audio D3 6 1/2 components Kicker 06ZX650.4 amp Kicker 06ZX2500.1 (x 2) DC Sound Lab Level 4 18's with Level 5 coils Autotek Mean Machine 400.1D (replaced) Soon to come: rims body kit flow master pipes Confuscious say "he who say it can't be done shouldn't be bothering man busy doing it" Now feel free to go crawl back under that rock and leave this to the professionals.... Link to comment Share on other sites More sharing options...
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