Competetion Box for my 2 12" RL-p (pic)

[DrtySthV6SE 10+ year member]

hi guys, wanted to post these plans up mainly for yall to make sure my calculations were correct and of course to check my mad ACAD skillz //content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

Ive got 2 cubes for each sub, net volume, without any bracing i might add

box total dimensions are 36" wide, 23" deep, 13.75" high, with 3/4 MDF

port area of 12.25"high*3"wide=36.75"^2 for each port

port length of 14.8" , measured from the end of the piece that splits the ports to the ends of the port walls, Is that correct??

i get a tuning freq of ~50hz which is probably kinda high, i might end up tuning down between 40-45, which would mean i will lengthen my port and increase my gross volume a little, correct??

i am open for any suggestions to make this box better

thanks

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[DrtySthV6SE 10+ year member]

anybody got any input, are my calculations correct??

 

[Buckshot 10+ year member]

2 Things that I see. What is the distance between the end of the "outer-port-walls" and the back wall? And, are you sure that center board is right?

 

[DrtySthV6SE 10+ year member]

the length is 4.5 inches from the port walls to the back wall, i noticed the closeness also but i wasnt sure if it was ok, if i tune a little lower i dont think it would be a problem. What do you mean "is my center board right", i put is there to seperate the ports and block the air/waves form interacting between each sub, is there a problem with it. Are my calcs ok so far

 

[saywhat? 5,000+ posts]

i think u should make 2 seperate ports. or one.....that goes straight back and T's on the back wall.

 

[DBfan187 5,000+ posts]

for SPL purposes:

keep the port straight - no bends

get more port area.

 

[DrtySthV6SE 10+ year member]

i do have two sepreate ports, my calculated length was not long enough to have it T off the back wall, if i had just one port for both subs there is a chance of cancellation, correct?? that is why i have two ports with the wall seperating them

let me change the dimensions and tune it a little lower and ill post another pic.

 

[DrtySthV6SE 10+ year member]

for SPL purposes:
keep the port straight - no bends

get more port area.

so you are saying what i have is good to go for spl purposes

 

[creater 10+ year member]

yea that looks alright by my view...his ports are straight...

 

[saywhat? 5,000+ posts]

but that middle port better come flush with the fron baffle....

 

[DrtySthV6SE 10+ year member]

i dont think it has too, just pretend like the part of the box between the end of the seperating wall and the front of the box is free air i.e. not part of the box, if i made it longer it would esentially lengthen my port,

thats the way i viewed it

 

[davidfre21 5,000+ posts]

but that middle port better come flush with the fron baffle....

its louder the way he has it //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[davidfre21 5,000+ posts]

oh yea, what vehical?

 

[davidfre21 5,000+ posts]

ahh a toyota, well only other thing i can think of is fire the port into the cabin. Even if it means having the port on the back of ur box

 

[DrtySthV6SE 10+ year member]

thats what i am going to do , the box is going to be made backwards in my trunk facing the cabin, with the seats down the subs and port should fit right in the hole between my cabin and trunk, believe me i have thought this out //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif