Is my box designed correctly?

[ckeeler11]

Those subs do appear to not want to get low but I would not worry to much about the response WinISD gives you. Once you put it in a car it will change drastically. In a vehicle this will get down into the 30's pretty well.

[BassAddikt]

16 hours ago, ckeeler11 said:

Those subs do appear to not want to get low but I would not worry to much about the response WinISD gives you. Once you put it in a car it will change drastically. In a vehicle this will get down into the 30's pretty well.

Yeah I figured that. I’ve read a lot about the program from what people say on here and I know that the graph is more of a generalization, and that it doesn’t account for cabin gain or anything like that. So I’m pretty excited to see what this new box is gonna sound like. I’ve already modeled it out in sketchup and I’m pretty happy with the turn out

[BassAddikt]

So, I sort of fixed the issue I was having with the rattling noise and turns out it was the screws mounting the subs had come loose...some were even broke in half 🙄 sooo, I put new screws in and it's all sounding alot better😁 HOWEVER,  I'm still confused about how small the port is and how there's not alot of port area. Previous replies has mentioned it doesn't have near enough port area for 4 15s. I asked the installer about it and he basically said his software showed that 45 sq in was apparently enough for the build. I 3d modeled his box, as well as one that I designed, so you guys can get an idea of what my box currently looks like, and maybe let me know what you think? Much thanks!   First one is my current box, subs facing up.

[Triticum Agricolam]

4 hours ago, BassAddikt said:

.... I asked the installer about it and he basically said his software showed that 45 sq in was apparently enough for the build.....

I don't know what to tell you other than the guy who built your box is just plain wrong.  45 sq in is not even half as much as you should have.  He messed up.  

The designs you came up with with the port on the side look good to me.  Just make sure your port is long enough to get the tuning you want, just from the pics it looks kind of short.  

[BassAddikt]

Thanks for the response. I wanna believe what my installer tells me cuz he’s a friend of mine but I’m well aware of how much you know about this stuff, as well as anyone else on here, and everyone on here talks about the “general rule of thumb” on port area which I know is just a basic starting point. But my point is that that goes against what my installer keeps telling me. And just to clarify- the first pic is the one my installer built (with the port in the middle. The length of that port is only 7.5”. The second design with the port on the top is the one I designed. The length of that one is about 14” tuned to about 34hz. My installer hasn’t seen my design but has already told me that he’d recommend not building a box “not knowing what I’m doing” because I could blow the subs. How likely would that be, exactly? I’d hate to blow them because I’m gonna eventually sell them to get some different ones in the near future lol

[BYTizzle]

Im not trying to insult your installer friend but I have a friend that owns a shop, builds custom enclosures etc.  I had him help me a several years back with a box for my Tundra (when I had that) in trade for me building him a website.  Seemed like a good deal to me, I didn't want to inhale saw dust at that point in my life and he was making a ton of custom setups in local cars.  So he measured the space and started building.  I asked him if the space was the 3 cubes I needed for the 3 subs.... he didn't know.... I then questioned if he knew how to calculate the air space even, the answer was no shockingly.  I stopped him so I could measure everything and make sure we weren't wasting our time.  Thankfully I did because the box he was planning to build would have been just over 2 cubes for 3 12's...

My point being, just because they do it everyday or for money even, doesn't mean they actually KNOW what they're doing other than filling a space with a box. 

[Triticum Agricolam]

8 hours ago, BassAddikt said:

... My installer hasn’t seen my design but has already told me that he’d recommend not building a box “not knowing what I’m doing” because I could blow the subs. How likely would that be, exactly? I’d hate to blow them because I’m gonna eventually sell them to get some different ones in the near future lol

How likely would you be to blow your subs with a different box?  Not very likely at all.  Two things kill subs, over excursion and overheating.  Too much heat is usually from sending them a clipped signal from an improperly set amp.  The box you have them in won't matter much.  Over excursion happens when you have subs in a box that is WAY too big, which shouldn't be a problem for you.  Or when you try to play content that is too far below the tuning frequency.  This shouldn't be a problem either as long as your tuning frequency comes out even remotely close to where you intend it to be and you set your subsonic filter properly.  Regardless of what box you have your subs in, you should set your subsonic filter on your amp a half octave below the tuning frequency to protect them from over excursion.

What it really comes down to is what blows most subs is how the amp is set, so if you are going to blow your subs, you are going to do it regardless of what box you have them in.  

I understand you want to trust your friend, but the situation is you have many, many sources saying he did things incorrectly and only one source saying he did things right, and that's him.  The fact that all your research you have done on the Internet has pointed to him being wrong and not a single piece has pointed to him being right should tell you something.  

[BYTizzle]

Spot on with every point!

Makes you wonder also, did this friend set the gain by ear?

[BassAddikt]

38 minutes ago, BYTizzle said:

Spot on with every point!

Makes you wonder also, did this friend set the gain by ear?

I also couldn't have said it better myself! And to answer that question, well...let me just say that his shop isn't professional by any means. He might as well be doing everything out of his backyard. So simple answer, yes. As far as I know, he doesn't use (or own) a distortion detector or anything like that. I've never seen him use one in any of his builds. So, yes, my gains are currently set by ear.