back mount depth ?

[Torrey]

ok so i know on ported sub enclosures you have to allow some space between the magnet of the sub and the back of the enclosure but on sealed enclosures is there a need for any space between? for instance if i have a sub with a back mounting depth of say 6" is it ok to build your enclosure 6 1/16" deep as long as you provide sufficient cubic feet with the width and length?

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[Falcons 5,000+ posts]

a little space is good. at least 2 inches. proper air movement. even though its sealed the air still needs to move in the box

 

[Moble Enclosurs 10+ year member]

ok so i know on ported sub enclosures you have to allow some space between the magnet of the sub and the back of the enclosure but on sealed enclosures is there a need for any space between? for instance if i have a sub with a back mounting depth of say 6" is it ok to build your enclosure 6 1/16" deep as long as you provide sufficient cubic feet with the width and length?

The main difference would be when the driver has a vented cooling system, where there is a small port you may see through the middle of the magnet. Other than that, if it is a sealed magnet, the difference is too minimal to notice audibly, even more with the right acoustical pressure, you could technically have the wall touching the back of the driver without any acoustical losses, but dont do that, because the baffle, with enough voltage to the driver, will flex and likely cause noise from the magnet hitting the port/wall structure, so, any amount of depth is ok with a sealed magnet, but a ported magnet, allow about 3" average to be safe for any driver. There can be a calculated figure for the pressure losses/gains at that single point and the noise it may cause, but not needed. Just use 3" to be safe with any amount of power/driver.

 

[RAM_Designs 5,000+ posts]

Easy answer:

Vented back plate on the motor = leave a couple inches

Solid back plate on the motor = doesn't matter

 

[Torrey]

okay in that case does anyone have a recommendation of a box i could use for my system?... the dimensions i have to fit my sub and box in is 20"L x 20"W x 11"H and i am looking at a Alpine 12" shallow mount sub that has if i remember right a 5 1/8" mounting depth. i dont want to build a custom enclosure so any help would be nice