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How hard is it to build a box?

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I can't stand these prices people are asking to make a box.

 

I think worst-case, can I pay someone to cut some MDF and I assemble the box myself? $200 for a 2.5 cube 12" box with no extra features seems pricey.

 

The only thing I don't have is a panel saw, but otherwise I have pretty much everything else.

 

Would it be hard to make a panel saw myself?

 

Would lowes/home depot cut mdf for me for a reasonable fee? I have also read that they will give you a new sheet if the cuts aren't perfect. (I won't mind 1/8" off, but if they aren't straight then that is a problem)

 

BTW I have 33x38x19 to work with and I want to tune to 28hz. Possibly aero port to save some room if neccesary.
 

The sub is a RE SX 18 (I think it's the new crappy ones cause it's very light) and I want 7-8 cubes if I can fit it in the car with the seats up

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Why in the hell do you need a panel saw?

 

For one, Lowes will cut for free.

 

Two, if it's not for cosmetics, all you need is a

table saw

circular saw

router

straight edge

clamps

pencil

Titebond III

clamps

clamps

clamps

 

IF you want to be real cheap

no table saw

no router

no clamps(lots of screws)

 

But how can you complain about a price when you have not the experience to do it yourself?

 

That would be like me going to the dealer and telling them i'm not spending $7,000 to have my engine replaced when I "hear" you can get it done for $3000 even though you can't find that person and you know not how to do it yourself.

 

Respect businesses and they will respect you.

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I'm not sure if the prices you are referring to are including shipping or not. But of course it is cheaper to build your own box. First you aren't paying labor which often includes overhead. Electricity insurance payroll and property taxes for example. Next you aren't building to make a living, to put food on the table.

I have tried the Lowes and home depot but often the cuts aren't straight. I find it is easier to just cut them myself.

I understand that you aren't happy about the prices someone sets. Therefore you don't buy that product, but it's far from someone trying to rip you off

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I'm not saying the prices aren't justified for most people, but for the work involved, it seems too high to me.

 

I do basic car audio stuff myself and for $100 per hour that most local shops want, it's ridiculous. People come to me and most of the time I just do the work and they give me trades or pay me later. I do it for fun. As long as they provide all materials needed.

 

I'm currently looking for someone near me to help me build a box that just does this on the side and isn't trying to make a huge profit.

 

Otherwise, I can build one myself. I just thought you needed a panel saw to get the cuts straight.

 

I mean I've looked up box building. For a simple design, it's very easy to put together. I figured most people would reflect that on their pricing, but no, they want to just make money. I guess most people don't do it for the hobby anymore.

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Even at 100$ an hour, shops aren't making a huge profit

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If you make a thread asking how hard it is to build an enclosure then you truly have no idea of the value of purchasing one it.   Simple as that and you can not argue it.

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I had home depot cut my MDF to my cut sheet specs.  they were pretty close- but not perfect.  I did clean up a fewedges- but I cound've built the box without cleaning them up 1/8" gaps...nothing to fill those with liquid nails.

 

Though honestly- i ended up with about 200 bucks in my 6' box tuned to 33, for my 18.  I spent 50 bucks Just on router bits.  it isn't cheap...and we spent a solid day on it.  And I'll say this- the Kaotic is a MUCH nicer box than I built.LOL 

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If you make a thread asking how hard it is to build an enclosure then you truly have no idea of the value of purchasing one it.   Simple as that and you can not argue it.

agreed

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Building a box is fairly easy if you have the tools. As shiz said. You can get by without a table saw or router. Measure twice, cut once. If you can cut a straight line with a circular saw you can more than likely construct a box. The design and specs of your box will be important. Watch a YouTube video or something. I think everyone should attempt their own enclosures at some point.

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I have been building my own enclosures for a while now, and have always used a circular saw and cutting guide, as mentioned, measure twice, cut once. But the one type of tool that made the biggest impact in ease of assembly, hands down, are bar clamps. Everything went together and lined up perfect. I cant imagine how else I would do it anymore. I also recommend corner clamps. Attach one board a little off, and its all screwed up. Sub enclosures need to be precise, they are one thing that has almost no margin for error. Takes time, effort, patience, thought, planning, etc.

Best of luck to you. 

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I am fairly confident with my skills to build a box. But I still want some personal help. I have made a few ads on CL and got a few replies so far. This one guy says if I get the plans, then he can build it.

 

I just need to help do one or 2 for some experience. I almost never need to build a box as I have a 12" 1.75 and 4.0 15" ported box which are pretty much good for any 12" or 15". But I decided to spring for an 18" this time.

 

i know, if I'm asking, then I can't do it. But I'm just asking as a reference.

 

I know it's not hard to build a box once you know what to do anyway.

 

What program is used to do the virtual sketch up?

 

Here is what I have so far in the RE box calculator.

 

I have it like this because I want it port up/sub up.

 

Is 9 cubes too much? Recommended is 5.5-8 cubes. I am going for killer low end response.

 

The measurements I have to work with are 38" width, 19" height and 33" depth. I would like to cut 3-6" off of the depth and 1-3 off of the height if possible (any combination is fine)

 

InPCnJ9.png

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How much power are you feeding the speaker? What is it rated for?

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How much power are you feeding the speaker? What is it rated for?

 

tl;dr 1k rms for each, I think.

 

2 ohm from a saz1500d v1. Sub is dual 3.2 (final 1.6) so I'm guessing right around 2 ohm after rise...800-1000w rms? It's supposedly rated for 1k rms but this sub feels like the cheap RE after the buyout of whatever so i'm guessing that is a generous rating.

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I think you should be fine with the large box, just set the gains appropriately and avoid the mechanical limits of the sub.

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I think you should be fine with the large box, just set the gains appropriately and avoid the mechanical limits of the sub.

 

I have my sundown @ 90% gain, with a pac lc-1 up front. The LC-1 is usually at half way and I turn it up for older songs, and down for decaf songs.

 

I have been running a $55 VVME RD-12 for a year, with no problems, and I've been abusing it under port tuning and it's still going strong. And that's with a 1.75 f^3 box when it supposedly need 2.5-3 cubes. I'm hoping that this RE isn't pure crap NEW RE because I would like to assume that it can hold up to more abuse than this $55 sub I've been abusing for a year.

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The RE box calculator is worthless.

 

With your box dimensions you need to calculate the enclosure volume taking into consideration the wood thickness, displacement of the driver, any bracing displacement, and port displacement. You also need to make sure your port area is adequate so you don't run into port noise. You also need to make sure your port length is correct for the desired tuning AND it's being calculated with the correct volume of the enclosure.

 

IE: the enclosure has an internal volume of 2 cubes. The sub has a displacement of 0.15cubes, so the internal volume is now 1.85 cubes. Say you want 30hz tuning and need 30in^2 of port area, and that calls for 15" of port length (these numbers are arbitrary) for 1.85cubes of volume, but the port itself displaces ~0.26 cubes, so your actual volume would be 1.59 not 1.85, which means the port length of 15" would actually raise the tuning, and you'd need to increase the port length to bring it back down to 30hz.

 

It's really not that hard as long as you know some basic math and have the ability to search around for what constitutes adequate port area.

 

It's also worth mentioning the above isn't even touching the subject of picking what enclosure volume and/or tuning would be best for an application, but rather just making a basic box.

 

I hope you design and build the enclosure all by yourself, that way perhaps you'll better appreciate the amount of work that goes into such and I won't have to read another one of your posts whining about peoples' pricing.

 

P.S. The RE calculator is worthless. If you use it and your box sucks, I told you so.

Edited by ssh

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The RE box calculator is worthless.

 

With your box dimensions you need to calculate the enclosure volume taking into consideration the wood thickness, displacement of the driver, any bracing displacement, and port displacement. You also need to make sure your port area is adequate so you don't run into port noise. You also need to make sure your port length is correct for the desired tuning AND it's being calculated with the correct volume of the enclosure.

 

IE: the enclosure has an internal volume of 2 cubes. The sub has a displacement of 0.15cubes, so the internal volume is now 1.85 cubes. Say you want 30hz tuning and need 30in^2 of port area, and that calls for 15" of port length (these numbers are arbitrary) for 1.85cubes of volume, but the port itself displaces ~0.26 cubes, so your actual volume would be 1.59 not 1.85, which means the port length of 15" would actually raise the tuning, and you'd need to increase the port length to bring it back down to 30hz.

 

It's really not that hard as long as you know some basic math and have the ability to search around for what constitutes adequate port area.

 

It's also worth mentioning the above isn't even touching the subject of picking what enclosure volume and/or tuning would be best for an application, but rather just making a basic box.

 

I hope you design and build the enclosure all by yourself, that way perhaps you'll better appreciate the amount of work that goes into such and I won't have to read another one of your posts whining about peoples' pricing.

 

P.S. The RE calculator is worthless. If you use it and your box sucks, I told you so.

 

OK I won't use the RE calculator. What should I use?

 

I really can't afford a $300 box. I have no choice but to make it myself.

 

I would be willing to pay for a legitimate blueprint though. That seems fair.

 

I admit, I don't know how to calculate any of the things you meantioned, but I can still put the box together myself at least.

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Yes well that is the trick. When you over power subs you stuff them in undersized boxes to limit their mechanical movement, which protects them from mechanical damage. After that you only have to worry about thermal damage which is easy enough to combat, when you start smelling things you turn down the volume.

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Won't a smaller box limit the low end response though? That has been the case with 2 12"s I have. I wanted to give it the full 8 cubes so I can get the most low end response out of the sub.

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The type of response you get will be related to the port tuning, and sufficient port area. 

When I attempted to make enclosures, I used Torres Box Calculator. 

http://torres-box-tuning-calculator.software.informer.com/

 

*Edit* Also, if you're not confident in yourself making your own calculations and or designs, for a small fee, most of these custom fabricators will make a design for you with cut-sheet dimensions. All you need to do is create the design using the specifications they gave you.

Edited by Hzd Skizzy

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Won't a smaller box limit the low end response though? That has been the case with 2 12"s I have. I wanted to give it the full 8 cubes so I can get the most low end response out of the sub.

It could but it could also be the tuning of the box and what your ssf is set to.

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A table saw is not necessary for enclosure building. I use a circular saw for my cuts. If you pick up a full sheet and don't have extra hands to help, wrangling it onto most home table saws is going to be very hard. If you don't have a steady hand and good eye with the circular saw then get a cut guide to run the saw with. You will be amazed how well this works. But you will want multiple work horses to support the sheet.

Home depot, Lowes etc... Will not guarantee there cuts as being dead on. It's posted right by their cut area, all cuts are rough cuts and may be up to 1/4" off... Which as with my local Rona that has a digital panel saw and 2 staff that were carpenters who just work the cut shop, it's complete b.s. that the cuts they make are as off as they make them.

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I am fairly confident with my skills to build a box. But I still want some personal help. I have made a few ads on CL and got a few replies so far. This one guy says if I get the plans, then he can build it.

 

I just need to help do one or 2 for some experience. I almost never need to build a box as I have a 12" 1.75 and 4.0 15" ported box which are pretty much good for any 12" or 15". But I decided to spring for an 18" this time.

 

i know, if I'm asking, then I can't do it. But I'm just asking as a reference.

 

I know it's not hard to build a box once you know what to do anyway.

 

What program is used to do the virtual sketch up?

 

Here is what I have so far in the RE box calculator.

 

I have it like this because I want it port up/sub up.

 

Is 9 cubes too much? Recommended is 5.5-8 cubes. I am going for killer low end response.

 

The measurements I have to work with are 38" width, 19" height and 33" depth. I would like to cut 3-6" off of the depth and 1-3 off of the height if possible (any combination is fine)

 

InPCnJ9.png

most use google sketchup for their 3d drawings

They use a combo of this an torres

http://www.soundsolutionsaudio.com/forum/topic/57107-how-to-design-your-box-in-google-sketchup/

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The Lowes, and Home Depot here must have there panel saws not setup right because they never give straight cuts(Or the employees are just careless and measure way off. I've found more luck with local lumber yards that have workshops, Ill buy 2 pieces of MDF and pay an extra $20 give them a cut list and they cut everything to spec perfectly. Also prevents me from having to worry about getting it home as I dislike the idea of strapping 2 sheets of MDF To the roof of my Jeep

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