Critique my box design.

[SGT_76]

Trying to come up with a box design that doubles as part of the platform for the bed in my sleeper. Enjoy a good laugh at my chicken scratch lol, it was the best I could do on my phone. It's for (2) dd9515/psi 15"s on a skar 4500, subs up, port forward.

 

What do you think?

 

[SGT_76]

Any input? Am I close? Thx.

[1point21gigawatts]

I would tune it to 31-33hz. Extending the port length a little bit should do it. Other than that, it appears to be a solid plan. 

[SGT_76]

On 4/30/2020 at 4:31 PM, 1point21gigawatts said:

I would tune it to 31-33hz. Extending the port length a little bit should do it. Other than that, it appears to be a solid plan. 

Thanks for the input. I'm actually thinking of either doing a removable port now, or an adjustable aero port, to ease tuning adjustments. I'm thinking that since the box will be in the sleeper (it's a 72" stand up Pete sleeper molded onto a reg cab Chevy Kodiak 7500), it is probably going to have a funky cabin gain. It could also "possibly" try and act like a series tuned 6th, since the entrance into the sleeper from the cab might act like the upper passband port/loading wall? Hmm... This actually has the old wheels spinning for "future possibilities" since I'm planning on gutting and redoing the whole sleeper at a later date anyway. Daily living in a huge 4th or 6th order would be different! One step at time, let's see how this turns out first lol.

[1point21gigawatts]

Same rule for an aero port too. If it’s a 6” aero, then it has to have 6” if distance between the exit point of the port and the hatch of whatever it’s facing and on the beginning point of the port inside the enclosure it has to have at least 6” in distance between that end and the inner wall it’s facing. Some people and even pre fab companies use less distance, like less than half the diameter. It can be ok, it all just depends on the location and variables of the port. And on the sides of the aero port there has to be at least 1” in distance between the port and the inner walls. Aeros have a better sound but if not done properly will have port noise. Making an aero port enclosure seems easier but it’s not as easy as people think because if that port isn’t done correctly there are multiple complications that can occur. But to sum it up into one nutshell of a complication... bad sound lol! 

[SGT_76]

23 hours ago, 1point21gigawatts said:

Same rule for an aero port too. If it’s a 6” aero, then it has to have 6” if distance between the exit point of the port and the hatch of whatever it’s facing and on the beginning point of the port inside the enclosure it has to have at least 6” in distance between that end and the inner wall it’s facing. Some people and even pre fab companies use less distance, like less than half the diameter. It can be ok, it all just depends on the location and variables of the port. And on the sides of the aero port there has to be at least 1” in distance between the port and the inner walls. Aeros have a better sound but if not done properly will have port noise. Making an aero port enclosure seems easier but it’s not as easy as people think because if that port isn’t done correctly there are multiple complications that can occur. But to sum it up into one nutshell of a complication... bad sound lol! 

Yep I know you have to watch out for "choking", thanks for ur input. I still consider myself a noob but I definitely enjoy learning. Honestly, whether I go the removable slot "square" port, or (2) 8" adjustable aeros will probably just come down to how much scrap birch I have left over. I have more than enough room to go either direction so it's all good. 

 

In the end it's possible that it might end up trying to act like a huge, disproportionate (like 10+ to 1), series 6th order still. If so I'll just get it playing as well as possible for the time being, and start planning the rebuild for when I gut and remodel the sleeper late '20/21. I've actually been looking around online at different companies "entry-level" subs (1K rms or less). I have A LOT of room to get stupid with, so a boat load of cone area in a 4th or 6th could be doable. I think large, loud "budget" sub builds are pretty cool. 

[1point21gigawatts]

2 8” ports to be tuned to or around lower or mid 30’s in frequency them ports would have to be 20-25” each. It would have to be about the same size if you get 1 10” port but would have a better sound and less chance of port noise. Plus you can put 1 10” port in the middle of the 2 subs like the slot in the first plan. I would just do one 10” aero port in the middle. 

[SGT_76]

18 hours ago, 1point21gigawatts said:

2 8” ports to be tuned to or around lower or mid 30’s in frequency them ports would have to be 20-25” each. It would have to be about the same size if you get 1 10” port but would have a better sound and less chance of port noise. Plus you can put 1 10” port in the middle of the 2 subs like the slot in the first plan. I would just do one 10” aero port in the middle. 

For my net box size and power, a single 10" aero is too small (that's actually where I started). A single 12" aero would actually be my preferred place to start. Given my box height & depth constraints, it isn't feasible though. (2) 8" aero's are still a tad smaller than I'd like to start with, but all things considered, if I do try the aero port route they will have the best fitment while keeping above my minimum port area (barely).

 

But like I said it all depends, I might just stick with a removable center slot port. It would definitely be the easiest (and fastest) to adjust tuning.