mj-18 box design help

[Tiiimay 10+ year member]

so ive read up plenty of making a ported box but im still rather confused. I got a copy of bassbox pro, and ive tried using the RE calculator but i keep running into problems. bass box kept telling me that my port wouldn't fit, but didn't give me the option of doing an L shaped port at all. when i finaly got it to work i drafted it up in solidworks and theres no way the port will fit and not interfere with the sub. but if it was a slot port it could, but that isnt an option in bassbox either If someone could help me out id really apreciate it.

I need 5cuft, tuned to 30hz. i was thinking of just a slot port on the bottom front face with the sub above that. if that doesnt work then port out the top. could someone just tell me some basic stuff to get me on my way or what im doing wrong?

Click to read more...

 

[mcsoul 10+ year member]

RE calculator can only do L-ports. I suspect that 5 cubes at 30hz will require a maze port ...er... a G port ... whatever you want to call the next port piece 3 or C.

Like what's going on here:

 

[Tiiimay 10+ year member]

well if i know the volume i need, and the tuning frequency, how do i figure out port width and length that i need to plug into RE's calculator?

 

[budahbuddy803 10+ year member]

well if i know the volume i need, and the tuning frequency, how do i figure out port width and length that i need to plug into RE's calculator?

just mess around with it to get your desired tuning frequency. It is almost self explanatory.

 

[THUMPPER 10+ year member]

be carefull with those labarynth ports...they can drastically lower the tuning

 

[Tiiimay 10+ year member]

alright im doing an L port, it fits fine cause of the massive volume. ive been going with the guess and check method on the calculator as sugjested. I just have one question. does anyone know the displacement of a mj-18? i cant find it.

 

[Tiiimay 10+ year member]

no body?

 

[RAM_Designs 5,000+ posts]

~.25ft^3