Box guru's come on in ***Testing completed

[Triticum Agricolam]

I'd suggest you try doing the sweep at lower volume, you just need enough power to get the subs moving like 1/8" peak to peak when you are above and below you tuning. It should make it easier to see where the cone moves the least. I'll often throw some sawdust on the cones so it easier to detect subtle movement.

I also agree with CleanSierra and think you would have been better to just put a 90 degree bend in your port and run it along the bottom to get the length you need. If you want to take some more drastic measures you might be able to knock out with a hammer the port panel extending up from the bottom and then add one in running sideways. Would be worth trying before you decide to build a new box.

[DubNDodge]

Port inefficiency would be my guess. I don't like ports(personally) that make a 180° turn.

You might have sounded louder before due to port velocity being high. It might have aided in loudness a bit because it was constricted.

Originally it was going to be a 90 degree turn. I was talked into a 180 by hunter. Yeah, my velocity before was pretty nuts. My passengers hair would be blown around by the port which was ~4 ft away, or whatever it was to the back of of the back seats.

Hunter designed it? It should be alright. As others have suggested, your cabin might be playing more of a factor into this than anything else.

A friend of mine designed it and I posted it up on my facebook with the 90 degree bend. The suggestions hunter offered was a 180 bend and a window brace. both of which were done.

I'd suggest you try doing the sweep at lower volume, you just need enough power to get the subs moving like 1/8" peak to peak when you are above and below you tuning. It should make it easier to see where the cone moves the least. I'll often throw some sawdust on the cones so it easier to detect subtle movement.

I also agree with CleanSierra and think you would have been better to just put a 90 degree bend in your port and run it along the bottom to get the length you need. If you want to take some more drastic measures you might be able to knock out with a hammer the port panel extending up from the bottom and then add one in running sideways. Would be worth trying before you decide to build a new box.

I'll try the sawdust lol. I tried this at many different volume levels, it was just a pain in the ass to see anything.

You and I are on the same page, that was my thought for my next modification. Hopefully jigsawing that port piece down the center will weaken it enough for it to be bashed out with a hammer.

That'll be next weekends project, there's a show I'm headed to tomorrow. Definitely not competing with a 144 lol.

[Triticum Agricolam]

Let me know what you find out with the sawdust test.

I'm sure if you cut that port piece down the center it will come right outta there with a hammer.

[walwalka]

I designed the box with recommendations from hunter and another box designer. I unfortunately went against my better judgement of these subs and designed it with a little higher air space and larger port as that is what Dubndodge wanted and what is the normal for 12s. These subs have a quoted .692 QTS, while I'm sure his own subs are different, based on his results and the results I had when I had the HDS312s.Small ported is what I feel these subs want, other than sealed and 4th.

My box for the HDS I went through a ton to get to work even remotely right. It was originally 5cu ft, with a single 8in aero so around 50sq in of port. I had similar results as DubNDodge who has 65sq in of port and 4.5cu ft originally. I also peaked at 37hz when I had that box, in a completely different car.

[DubNDodge]

Well I didn't make he port a 90 degree. I decided to just do a port plug because I thew my old one from the stratus in there, and it sounded better lower.

managed to put a drill bit through the surround putting the sub back in, so that put my over the edge. fuck this box. fuck these subs. new build time.

[Triticum Agricolam]

That sucks about the bit through the surround. That's one of several reasons why I like to use socket head screws or square drive.

So it sounded better with the lower tuning though?

[DubNDodge]

Yeah to some extent. It definitely reached below 30Hz better. Plus after my buddy listened to it today, we both agreed I'm throwing way too much power at the subs. I can crease the cones with ease.

On my ride home from his place, instead of trying to run the absolute piss out of them, I ran them moderately and the bandwidth is really rather fine. I guess I just expected too much out of everything and was biased from the get go.