Fi Q Enclosure Design

[bjs810 0]

How do these dimensions look for my Fi Q12 d1

Box outside diameter after using 3/4" MDF:

Box: 33.5 x 14.5 x 12

Port: 1.5 x 13 x 16.5

This should give me 2.53 ft3 (before taking away sub/port displacement) and be tuned to ~32 Hz.

I have been using website like the12volt.com and a couple others. I tried the RE enclosure app, but

I think it is a little off. Not too sure. I appreciate any help! If this box looks off, what would be better?

Thanks.

[NB50 206]

After all displacements that enclosure will be 2.11ft^3 @ 34.5 hz.

[sadistic 13]

After all displacements that enclosure will be 2.11ft^3 @ 34.5 hz.

hay bromo i get 2.19 at 34.5 hz lol's i think the 2.11 was a typo just say some thing if it is not. it not worth learning unless you learn it.

i used a port that was 1.5 x 13 x 20 it came out to be 31.84 hz it close enough to be right on the money because of rounding here and there in the same box out side dia 33.5x14.5x12 inside dia is 32x13x10.5 divide by 1728 give aprox 2.53 cuft minus sub .16 displacement and port displacement of .186 equals 2.19 cuft .

if you play a good test tune threw it it will fell like it's correct. tuned right at 32 seen a few manufacture's tune lower because it sounds better and they round up to the first ones place.

[sadistic 13]

http://www.ecalc.com/calculator/scientific/

use this calculator at link above

square root key look like a check with a x inside

powers of ten key looks like a y to the power of x

av =10

lv=30

vb=864

do the this part first av(1.84x10to the power of key looks like y sub x when the calculator does the y to the power of x key it will put some thing that looks like a up side down carrot.

Then write the answer to all of the above down

Next do vb(lv+.823then hit the square root key put in av then write the answer down

Take the first answer and divided buy the second one

Then take and put in to the calculator .159 square root of the answer of the two this should equal 40.63716007346 hertz for the fb

Just remember you can plug any thing you want into av or lv or vb that the plug part

Av =a 2 inch by 10 inch wxh or area of vent

Lv = length of vent

Vb = volume of box

just try to keep the area of the vent less then a 9 :1 just divide like a 10 by 5 inch port in to this 5/5 and how many section of ten you get and 10 /10 and how many section of 5 you get this would equal 1x10inch and one 1x5 inch the 1x5 would pass but the 10x1 would not it to big

here are some other formulas

pie times radius squared

radius is half of a circle and this trans forms a round to a square vent real quickly

square root of

[sadistic 13]

this is were the formula is from and and has a little more info on it at link

http://mobile.jlaudio.com/support_pages.php?page_id=165

[NB50 206]

After all displacements that enclosure will be 2.11ft^3 @ 34.5 hz.

hay bromo i get 2.19 at 34.5 hz lol's i think the 2.11 was a typo just say some thing if it is not. it not worth learning unless you learn it.

i used a port that was 1.5 x 13 x 20 it came out to be 31.84 hz it close enough to be right on the money because of rounding here and there in the same box out side dia 33.5x14.5x12 inside dia is 32x13x10.5 divide by 1728 give aprox 2.53 cuft minus sub .16 displacement and port displacement of .186 equals 2.19 cuft .

if you play a good test tune threw it it will fell like it's correct. tuned right at 32 seen a few manufacture's tune lower because it sounds better and they round up to the first ones place.

Nope no typo. Your port displacement is to small, you need to remember to take the inner port wall thickness into account when figuring port displacement. Also bjs, I would consider more port area if you can.

[bjs810 0]

Awesome thanks for your time guys. I appreciate it. I'm gunna play around with those websites you listed. Bromo, what would the correct port size be? I have plenty of room for my box. It will be in the back of a Tacoma ext cab. The area is around 16 x 18 x 48, but I don't need a box that big obviously. If anybody has box/port specs around the 2.5 cu ft mark and 32 hz please share. I want to build a box asap.

Edited June 12, 2009 by bjs810

[Duran 387]

Awesome thanks for your time guys. I appreciate it. I'm gunna play around with those websites you listed. Bromo, what would the correct port size be? I have plenty of room for my box. It will be in the back of a Tacoma ext cab. The area is around 16 x 18 x 48, but I don't need a box that big obviously. If anybody has box/port specs around the 2.5 cu ft mark and 32 hz please share. I want to build a box asap.

I recommend at least 30^2in. port area. If you want more output do more port, but no more than 40^2in.

[NB50 206]

Something like this.

[bjs810 0]

Thanks a million Bromo. I'll let you know how it turns out.