Box specification help.

[Thewes 2]

For the BL 15's it says 4 cubes max for each sub, so if I have 2 it would just be 8 cubes, no strings/formulas attatched? Also, the more cubes the better, correct? And lastly, I was thinking of tuning to about 33, anyone have some advice on this? Thanks

[theabunai 3]

Careful on the "more cubes the better" there is a point (as with smaller enclosures) that it begins to have a negative effect on the performance of the sub... Generally i would recommend you stay within the limits of Fi enclosure specs...

Yes 8 cubes would be correct for 2 15" BL's Note that this is after all port and sub displacement...

32 - 30 hz is a good round about tuning for 15's in a DAILY application... if you are just using them for Daily then go for it... for SPL and Competitions you may want to go higher into the 40hz range...

[Thewes 2]

Thanks, but can you go into more detail when you say with sub displacement and port? For example, I was thinking hopefully the box I have made would be like 4x2x1. Would I have to make the box larger to make up for the displacement of the subs?

[theabunai 3]

displacement of the subs can be found on the Fi website..

for example the website says "displacement .19"

so in order to get a 4.0 cu^ft airspace for a single 15" Q you need to make the box have an internal volume of 4.19 cu^ft since .19 is taken by the sub you have 4.0 left over...

this is the same with the port..... figure out port length first... then figure out port area and add that to the airspace + the subs displacement and you'll have the box size you will need BEFORE displacement...