Calculating Volume Of not a Square Object.

[cheese20323 13]

So As I've been tired of looking at how my subwoofers look,(well the looks), then I've decided to make a custom ported box...only difference I'm going to fiberglass it so it's not going to be cubed anymore...so I'm trying to find out my volume so I can calculate all the port things...

[shizzzon 461]

you could do like us competitors do..

Trial and error your port tuning.

Although, since you are aiming for daily, which is a lot easier, just build you the longest port u can get in there and see how it sounds. Start cutting a little off at a time if you think it's tuned too low until you get it how you want it.

[dj00140 0]

No silly, get a 12x12x12 box or any rectangle box you can calculate the volume of, fill it with packing peanuts, if your box is 1 cube and you need 3 boxes to fill your fiberglass box then it is 3 cubes...

[Julian 641]

No silly, get a 12x12x12 box or any rectangle box you can calculate the volume of, fill it with packing peanuts, if your box is 1 cube and you need 3 boxes to fill your fiberglass box then it is 3 cubes...

good idea.

[cheese20323 13]

you could do like us competitors do..

Trial and error your port tuning.

Although, since you are aiming for daily, which is a lot easier, just build you the longest port u can get in there and see how it sounds. Start cutting a little off at a time if you think it's tuned too low until you get it how you want it.

Alright well since I'm aiming for about 3.5 cubes...net..so .10 for the subs and ballpark about .25 cubes...leaves me at about 3 cubes...around their ...and the port I'm guessing..a 6.5x6.5 for about 38 sq inches of port area if not more...so make the port about how long?

[ssh 924]

What type of fiberglass enclosure are you going to do? like design or look wise. Depending on shape you could still use basic geometry to get a pretty good estimate of volume. Or you could always try the packing peanut idea, it should be close enough.

[cheese20323 13]

What type of fiberglass enclosure are you going to do? like design or look wise. Depending on shape you could still use basic geometry to get a pretty good estimate of volume. Or you could always try the packing peanut idea, it should be close enough.

well i would like to just have the bottom, side, top, back..MDF, then i would just like the front fiberglassed..with tilted subs port in the middle..my estimate would be about 3.5 cubes...Don't have packaging peanuts so I just have ballpark numbers or any other ideas....

[ssh 924]

What type of fiberglass enclosure are you going to do? like design or look wise. Depending on shape you could still use basic geometry to get a pretty good estimate of volume. Or you could always try the packing peanut idea, it should be close enough.

well i would like to just have the bottom, side, top, back..MDF, then i would just like the front fiberglassed..with tilted subs port in the middle..my estimate would be about 3.5 cubes...Don't have packaging peanuts so I just have ballpark numbers or any other ideas....

Sounds like it's going to be 99% rectangular shaped, so volume measurement should be easy to attain

[cheese20323 13]

What type of fiberglass enclosure are you going to do? like design or look wise. Depending on shape you could still use basic geometry to get a pretty good estimate of volume. Or you could always try the packing peanut idea, it should be close enough.

well i would like to just have the bottom, side, top, back..MDF, then i would just like the front fiberglassed..with tilted subs port in the middle..my estimate would be about 3.5 cubes...Don't have packaging peanuts so I just have ballpark numbers or any other ideas....

Sounds like it's going to be 99% rectangular shaped, so volume measurement should be easy to attain

pretty much..I think I have it figured out..

[dj00140 0]

If anything make it a little big and you can drill 2x4's into the bottom corners, it will add bracing and you can use them to adjust volume!

[Godsmack 361]

Adjust volume with 2x4's?

Seriously?

UN COOKED rice works well here too but can get kinda heavy.

J

[///M5 2,833]

you could do like us competitors do..

Trial and error your port tuning.

Although, since you are aiming for daily, which is a lot easier, just build you the longest port u can get in there and see how it sounds. Start cutting a little off at a time if you think it's tuned too low until you get it how you want it.

Wow, the competing near you must be like taking candy from a baby Trial and error is only for fine tuning IMO, physics will dictate the rest. I would never arbitrarily build a box with an ultra long port and trim it.

Alright well since I'm aiming for about 3.5 cubes...net..so .10 for the subs and ballpark about .25 cubes...leaves me at about 3 cubes...around their ...and the port I'm guessing..a 6.5x6.5 for about 38 sq inches of port area if not more...so make the port about how long?

Problem is "guessing" and "guessing" equals NO CLUE on how long the port should be.

-packing peanuts

-rice

-sand

-water

are all fine mediums for measure. Just make sure your glass is dry so stuff doesn't stick to it like hell. Obviously if you have no exposed wood, the water method is the easiest.

[cheese20323 13]

you could do like us competitors do..

Trial and error your port tuning.

Although, since you are aiming for daily, which is a lot easier, just build you the longest port u can get in there and see how it sounds. Start cutting a little off at a time if you think it's tuned too low until you get it how you want it.

Wow, the competing near you must be like taking candy from a baby Trial and error is only for fine tuning IMO, physics will dictate the rest. I would never arbitrarily build a box with an ultra long port and trim it.

Alright well since I'm aiming for about 3.5 cubes...net..so .10 for the subs and ballpark about .25 cubes...leaves me at about 3 cubes...around their ...and the port I'm guessing..a 6.5x6.5 for about 38 sq inches of port area if not more...so make the port about how long?

Problem is "guessing" and "guessing" equals NO CLUE on how long the port should be.

-packing peanuts

-rice

-sand

-water

are all fine mediums for measure. Just make sure your glass is dry so stuff doesn't stick to it like hell. Obviously if you have no exposed wood, the water method is the easiest.

alright, so no water because there is MDF so it will expand if in contact with water, I will end up doing sand because it is what I find easier...so let's say 3.5 from sand -.20 from subs then like another .20 from port...then calculate the port needed and and bracing and all that fun stuff.

[Impious 1,476]

Really, if all you are doing is angling the subwoofers some on the front baffle I really wouldn't worry about measuring the small difference in volume unless the fiberglassed section ends up being extreme and adds significantly to the area of the enclosure. In the grand scheme of things, a few tenths of a cubic foot in a 3.5cuft enclosure is not going to make one bit of audible difference.

[shizzzon 461]

you could do like us competitors do..

Trial and error your port tuning.

Although, since you are aiming for daily, which is a lot easier, just build you the longest port u can get in there and see how it sounds. Start cutting a little off at a time if you think it's tuned too low until you get it how you want it.

Wow, the competing near you must be like taking candy from a baby Trial and error is only for fine tuning IMO, physics will dictate the rest. I would never arbitrarily build a box with an ultra long port and trim it.

I'm serious, lol. It depends on what type of install one is doing but for his, that's how EVERYBODY does it, not just around here.

I'll break it down into two classes-

trunk or cargo\ wall.

If building a typical box, we, competitors, build a port that can be cut and cut and cut until one reaches their maximum output potential..

For a wall, it's the complete opposite. One would build a bare wall with no port length and if tuning is too high, a competitor will add another internal layer to the baffle... and so on and so on...

that will decrease volume but add port length too( sounds like you are getting no where but it does help...)

If a competitor chooses not to do that, 2x4s added to the port length works too then just glass over them for a smooth finish...

For a bandpass design, once it's built, competitors actually build a no port length to the outer chamber.. To tune it, they simply just decrease the forward-most chamber's volume by adding a layer of wood to it again and again until it peaks the way they want it.

I know u used to compete but, hehe, if u have some insight.. as to how this is completely wrong, then you would be bringing on a whole new meaning of tuning a box for competition if u know what i mean.. You'd stop everybody in their tracks... It's the norm everywhere i've ever seen and been around and i've been to many shows.