the new box will be the same volume as the old box, with the port from that box, so in theory shouldn't even be able to tell the difference
Same sub, same volume box, same port, different shape, same sound?
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Same sub, same volume box, same port, different shape, same sound?
the new box will be the same volume as the old box, with the port from that box, so in theory shouldn't even be able to tell the difference
What box and sub.
If say at a guess you make a perfect cylinder 20" Diameter x 8" High and 0.75" thickness of wall then thats just 1cu ft of Airspace.
With the same height to get anything near a decent size for a sealed enclosure you will need a diameter of 26" getting 1.78 cu ft before displacement.
Then if you are going to port to tune to 40hz a 4" wide port needs to be 9.5" long.
The post displaces 0.05Cu ft so that really is nothing to worry about but i would check that i have calculated the port displacement properly it seems rather low.
All of the above is assuming that the sub is inverted.
If say at a guess you make a perfect cylinder 20" Diameter x 8" High and 0.75" thickness of wall then thats just 1cu ft of Airspace.
With the same height to get anything near a decent size for a sealed enclosure you will need a diameter of 26" getting 1.78 cu ft before displacement.
Then if you are going to port to tune to 40hz a 4" wide port needs to be 9.5" long.
The post displaces 0.05Cu ft so that really is nothing to worry about but i would check that i have calculated the port displacement properly it seems rather low.
All of the above is assuming that the sub is inverted.
P.S if you make it using these specs it will sound better than the original. 
P.S if you make it using these specs it will sound better than the original.
no offence or anything but why do you think those specs make it any better? when you don't even know what sub and amp it is
my new box will be the same volume as my old box only a different shape, and the port is actually bent into a right angle, so it is very long but doesn't take up much room, it is the same port from my current box
the sub btw is only a 12" fusion enclosure, bought it when i couldn't do with spending more on a sub than the car was worth (L reg polo) but then never felt the need to upgrade it so don't want any digs at it lol, it does the job:slayer:
anyone tried making a round box before? any lessons learnt or words of wisdom?
EDIT:
btw the actual volume is 1.76
Last edited:
EDIT: btw the actual volume is 1.76
You forgot to take out the volume of the external thickness of wood. It is Internal volume that you need to work out
I woked the edge of the box as 0.5" i think but cant remember also So the 8" Height i used is actually internal height so the box you make will actually be 9 1/2" tall if you use 3/4" MDF for base and lid (which i recommend as a minimum)I have seen, installed and read post's of very similar things many many many times so sometimes you just know what kind of sub a person has and what would be best for that sub by having at least some knowledge of the TS parameters. So i can have a pretty good stab at showing you the kind of things you will need to do to make this new enclosure better than the crap prefab ones that you get with the packages.
I didnt really mean use those measurements as they were just a rough guess using the minimum TS parameters for a JBL 12" sub. Some may say the JBL sounds better than yours, but the parameters as a rule of thumb are very similar.
I dont need to know what amp you are using as that doesnt have a great deal to do with the design of the enclosure.
I am trying to give you words of wisdom about designing a round box and yes i have done it recently.
The port is very important as this will be the tuning of the box and should be designed with the box in mind. The prefab ones are well known for port noise due to increased port velocity due to port area hence why i say to use a 4" port.
No one will take a dig at your sub as its not the worst and if your happy with it then thats your perogative.
sorry last post wasn't clear, the actual volume i'm using is 1.76, wasn't taking a hit at your calc's
although on further inspection the prefab has a divider in it a didn't take into account, gonna work that out tomorrow but will prob make it a little bigger,
how you made round boxes before? i'm thinking my idea will work but not gonna know till i've tried
although on further inspection the prefab has a divider in it a didn't take into account, gonna work that out tomorrow but will prob make it a little bigger,
how you made round boxes before? i'm thinking my idea will work but not gonna know till i've tried
So yes my calculations would make the sub sound better more importantly getting the port correct will make a massive improvement.
Also i recommend that you make the inclosure a bit closer to 2cu ft if you can buddy.
The enclosure that you normally get with the fusion packages are crap so its not very hard to improve upon the original.
Considering i hadnt known any info i dont think that was a bad guess, normally when people can do that, its a good sign that you should listen to what they say.
Normally when building a wheel well enclosure i have designed them using Fiber glass so i dont know a lot about ply so cant give any tips there.
I would imagine that you have to use Plexi Pli which has slots in it so isnt very strong so i would still use quite a lot of FG and deadening material to reinforce it.
Have a little read on Resonance it will tell you why you need a solid enclosure.
Also i recommend that you make the inclosure a bit closer to 2cu ft if you can buddy.
The enclosure that you normally get with the fusion packages are crap so its not very hard to improve upon the original.
Considering i hadnt known any info i dont think that was a bad guess, normally when people can do that, its a good sign that you should listen to what they say.
Normally when building a wheel well enclosure i have designed them using Fiber glass so i dont know a lot about ply so cant give any tips there.
I would imagine that you have to use Plexi Pli which has slots in it so isnt very strong so i would still use quite a lot of FG and deadening material to reinforce it.
Have a little read on Resonance it will tell you why you need a solid enclosure.
made a start today, think the wood round box is gonna work have a look below, only got 3 of the 6 slats in there so it isn't perfectly round yet, + once i've glued it tomorrow i'm going screw them together till there dry
this is the base with the sub and port in it
i've not yet started the box but i've made the Jig to use, i've put a few slats in so you can see how it will work
this is the base with the sub and port in it
i've not yet started the box but i've made the Jig to use, i've put a few slats in so you can see how it will work
finished it off this weekend, i built around the bracket in the bottom of the well, this gave me an xtra 2" depth, the floor is now 2" higher than it was, with 1 1/4 inch foam inbetween the boot floor and false floor, the drum its self is floating independently down from the false floor in the well, with padding just in case it does move it won't bang against the side of the well
then mounted the amp on the box on the left hand side, with gaps in the top for the compressor, tow eye and locking wheel nut keys
i'm just waiting for the grill to come from ebay to put over the top of the sub and i've got one to go over the top of the port as well, and i've got MILES more boot space than before
How does it sound dude.
Sweet
although different, its sounds warmer than before, and i havn't put my finger on it yet but it just seems to fit into the spectrum better than it did before, its less obvious than it was, but only in a good way it certainly hasn't been lost
it was a bit of a nightmare making the drum, it needed 6 hands lol, only point i would make if someone else was trying, or i was making it again (i would make it this way) is that the posts in the jig need to be have at least two wood pegs in the bottom, glued and screwed as the're under so much pressure when the wood's in there
other than that it went a dream
just got the badge and grill delv today, going to dremel out the grill so that the badge sits into it slightly, heres a preview
although different, its sounds warmer than before, and i havn't put my finger on it yet but it just seems to fit into the spectrum better than it did before, its less obvious than it was, but only in a good way it certainly hasn't been lost
it was a bit of a nightmare making the drum, it needed 6 hands lol, only point i would make if someone else was trying, or i was making it again (i would make it this way) is that the posts in the jig need to be have at least two wood pegs in the bottom, glued and screwed as the're under so much pressure when the wood's in there
other than that it went a dream
just got the badge and grill delv today, going to dremel out the grill so that the badge sits into it slightly, heres a preview
LOL at that port it cant be more than 1cm long you would probably get a better sound by not having it.
lol thats just the flange, found a vibration, it was the pipe on the port, the two halfs have come apart at the joint, taken it out to glue, will be putting it back in this weekend
Ahh that makes more sense lol.
