6 lvl 3 15s in 4th order

[02gmc92dcaudio]

I would like to know how many cubes sealed would you say per sub in a 4th order

For level 3 15s on dd m4a

[CJSmith]

Welcome to the forum. Out of curiosity, what is your electrical like? Batteries, alt(s), wiring, etc.

And what do you mean sealed? A 4th order is ported. Are you talking about the sealed part of the 4th order design? I'm not great with box designs, but their website says 2 cubes sealed per 15, so 12 cubes. The front of the enclosure however, needs to be larger.

Edited March 6, 2013 by CJSmith

[02gmc92dcaudio]

Thank, and i have a mechman 270a, 5 ups 12-400mr, 3 runs + and - . And ya sealed side.

[02gmc92dcaudio]

So is 2 cubes per sub seald good for in a 4th order or little smaller

[CJSmith]

So is 2 cubes per sub seald good for in a 4th order or little smaller

I'd go with 2 cubes per sub on the sealed part of the enclosure. Maybe a hair bigger if you know what your doing.

[mrd6]

The size of your sealed side has to do with what you want to tune the 4th to and your ratio and goals etc...

[02gmc92dcaudio]

Ok i like it to play low but still have the high end, i have the room for a 2:1 or 3:1

[mrd6]

What do you consider low? Like 28hz or 20hz lol. Do you care about numbers at all?

[02gmc92dcaudio]

20hz -mid 40s is what i want to play and ya kinda care about numbers .

[mrd6]

Look at tuning lower then around 43hz, with a 2:1 ratio you should crush that frequency range and still have a nice roll off up in the mid 50hz area.

You want your sealed chamber to be whatever size causes it to have a sealed resonance the same as your tuning. Or another way of looking at it, you want your sealed impedance peak to be at your tuning frequency. Some box building software will be able to get a good estimate on what size sealed enclosure that would be but imo if youre investing this much into the build I would build up a small test sealed enclosure for one of the 15s and measure it until you find the correct size sealed per 15. It will probably be around 2 cubes but even being .25 cubes off in eaither direction can hurt your output by a few dbs. So be ready to test!