If your interested in finding out the size of the correct speaker enclosure, generally speaking the recomended volume in cubic feet or litres is generally given with a spec sheet with almost every sub Ive ever seen, including recomended port legths and diameters.  You only need to work out the amount of air you need to enclose
 
for example
 
A sub box recomended to be 2 cubic feet of enclosed air could be
1 foot high by 1 foot wide by 2 feet long
 
ie:  multiply the height * width * length  (make sure your figures refer to the internal space not including the width of the material used)
 
Within reason you can squash and play with the sizes as long as your internal volume remains the same
 
ie 1 foot = 304.8mm  therefore 304.8 * 304.8 * 609.6 =  56633693mm total volume
 
therefore to make a box the correct size given two of the sizes you want ie: the height (400mm) and the width (600mm)  the other side would be got as follows assuming the enclosure still needs to be 2 cubic feet
 
400mm * 600mm = 240000mm
 
therefore missing size = 56633693mm divided by 240000mm  = 235.97mm
 
so your box would be 400mm by 600mm by 236mm
 
Accuracy is important so try and get your box within 5% of the recomended volume. 
 
Please also note once building the box you will have to add the thickness of your material to some of the sides to keep the internal volume correct
 
hope this has been usefull
 
Cheers
Lee MKII 1G-GTE (missing one turbo)
----- Original Message -----
From: Brendon Vincent
To: Supra Club of NZ Mailing List
Sent: Wednesday, March 31, 2004 11:22 PM
Subject: Re: [sconz] Sub brands

anyone know of formulas or websites or where to get other info on just how big a box should be?
 
Brendon
----- Original Message -----
From: Lee Dobson
To: Supra Club of NZ Mailing List
Sent: Wednesday, March 31, 2004 10:15 PM
Subject: Re: [sconz] Sub brands

Actually I'd probably say good gear is only about half the battle the idea is to have a tuned box, ported or sealed, the tolerance is about + or - 5% of the recommended volume to have the resonant frequency at its peek, more than 5% either side and a good set of tens or a single 12 will produce more punch or rumble.  In short if you make a box too small you can restrict the movement and get a tighter sound but loose overall efficiency, if you box is too large you'll allow the speker to travel to far and not only get a muffly poor sound but possibly damage the speaker over time
 
food for thought
 
Cheers
Lee MKII 1G-GTE (missing one turbo)
----- Original Message -----
From: Toy Performance Headquarters
To: Supra Club of NZ Mailing List
Sent: Wednesday, March 31, 2004 9:18 PM
Subject: Re: [sconz] Sub brands

ok, 15's are good if they'r tuned right, and believe me, there aint that many people out there that can tune them proply that ive found...
i used to own 2 15' rockfords, and they sounded mint in and out of the cabin, its all in the tuning on the heady and amp...
 
Libby Cameron
Toy Performance
www.toyperformane.org.nz
----- Original Message -----
From: Hunt M
To: Supra Club of NZ Mailing List
Sent: Wednesday, March 31, 2004 9:13 PM
Subject: Re: [sconz] Sub brands

15's i've been told are a little "slow" and no so good in the cabin - sound good for the outside world and thats what some people want but not me.
2 15's is what I was starting to think but I dunno.......3 or 4 12's would be cooler ;-) altho budget is going down hill fast.....
 
----- Original Message -----
Sent: Wednesday, March 31, 2004 9:07 PM
Subject: Re: [sconz] Sub brands

ok, not everyone will agree with me here, i already know that...
 
my bets would be 15's. one or 2, up to u
and brands probly go for fusion powerplants, rockford fosgate, they'r both rumbly subs and got a lot of power behind them
 
Libby Cameron
Toy Performance
www.toyperformane.org.nz
----- Original Message -----
From: Hunt M
Sent: Wednesday, March 31, 2004 9:07 PM
Subject: Re: [sconz] Sub brands

rumble rather than punch - like dr dre kinda beats and people under the stairs (people under the stairs - acid rain - download and listen to that) - bass like that
 
----- Original Message -----
Sent: Wednesday, March 31, 2004 9:02 PM
Subject: Re: [sconz] Sub brands

depends what ur after... punch, rumble...
 
Libby Cameron
Toy Performance
www.toyperformane.org.nz
----- Original Message -----
From: Lee Dobson
Sent: Wednesday, March 31, 2004 8:08 PM
Subject: Re: [sconz] Sub brands

I have all pioneer gear in my car including a 12" DVC sub,  Ive always found their equipment to be reliable and well produce, with clear sub bass sounds when the box is built to the "Q" of the speaker
 
Cheers
Lee MKII 1G-GTE (missing one turbo)
----- Original Message -----
From: Hunt M
Sent: Wednesday, March 31, 2004 8:03 PM
Subject: [sconz] Sub brands

Hey all,
Who makes the best subs - 12's and 15's
Opinions apreciated
 
Hunt
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