CFD

@1point21gigawatts thnx for watching my video I design quite a few boxes. I'm not bad at it. I cleared up a misconception I had and figured others may have that misconception so I posted about it. Don't act like I'm stupid. I'm not. Box designs I've made since then have been perfectly fine. No need to bash people on here.

Yeahp. I messed that up for a long time and was left scratching my head on why my subs didn't sound exactly as expected. Figured it out recently and un-dumbassed myself. I designed a box for a guy for $10 but that was just cut sheets for the box. I would design it and put it on ebay.

6th order for a Dayton Audio Ultimax 18

Get WinISD if you don't already and put your speaker's specs into it. Play around with the volume of the sealed chamber and the volume/tune of the ported chamber until you like what you see. I think the sealed chamber should be about the same size as recommended for a sealed box, but you can have some variance. Don't worry about the 4th order peaky peakness. It'll be there, but I think it's not a bad thing. Sealed boxes have a similar peak, but you won't really notice that much by listening to it, you know? Same thing with ported boxes just about anywhere above the port tuning. 6th orders are the only boxes I've seen where I could get an almost perfectly flat response (according to WinISD). Point is, peak is there, but who cares? Probably not you. I could help you with a design and try my best to tell you what I know but I'd need more info.

You can add some poly-fil inside the box to make up for the lost air volume from the fiber glass and resin deal if you go that way. That stuff won't take that much space, but it might be good regardless. Boxes under a seat are probably under sized for a lot of subs. Good Luck

1.2 cu. ft. (before sub displacement) ported box for 2 6.5 inch woofers tuned to 40 Hz, again, before displacement. 4.6 cu. ft. (before sub displacement) big old big giant big port 12 inch subwoofer box tuned to 26 Hz. WinISD plot of that box with a Power Acoustik GW-124

Here's a bunch of videos of things I did that you can go ahead and call me an idiot about You could probably turn this into a sealed box and it might work better... or fire the ports out of the bottom into the side of the quarter panels in the trunk instead of out the front. It worked OK I think. Volume was small for these subs hence hella poly-fil. Could be good for some 10's? Whatever ya want https://www.youtube.com/watch?v=IYaVAQFsh3Q Basically a 12" Pre-fab box because I totally fucked up. About 1.65 cu. ft. and 43 Hz tuned. Ignore the guy in the video. He's an idiot. https://youtu.be/imBUMGm0cOw Box for a couple 12's. Super big AF. 6.6 cu. ft. tuned to 25 Hz. The guy in the video was wrong about the air volume because he is an idiot. https://www.youtube.com/watch?v=RbnhrJhuc3o Video explaining on why every ported box I've ever made was wrong and how massive of a moron I am (just so you know) https://www.youtube.com/watch?v=tULd3XlysAM I'll probably post more CFD Designs in this thread as time goes on.