Will this work if I do this to my port?

[Davo2378 0]

OK as of right now my box this like this.

And now I wanna do this to it, if I take 1" out of the top and make it 18" tall it will make the box 7ft^3 net,

and now i take 3/4" mdf and put is on the inside of the port and make the port 4.5H by 18.5W and keep it 16.5D

It should tune it to 35Hz.

The red is the new MDF in the port

can I do this and will it work?!?!?

[xAndrew225x 8]

It should work but that isn't near enough port area. For my taste at least...

[Davo2378 0]

it has right now 120in and almost 39Hz and i dont know but it just dosent sound right to me,

but i will say that rock music sounds great on it but thats about it, i think its just tuned to high.

[NB50 206]

Right off hand you internal volume and tunning is going to be different then what it shows if you change it like that. Why, because you will have the displacement of the 6X20X16.5 port instead of what it is using to figure out displacement (4.5X18.5X16.5).

[Davo2378 0]

it should be fine i think, By taking the inch out of the box that makes the box 7ft^3 net on the inside,

so then i put 7 in the box for DESIRED NET VOLUME on the calulater,

then chang the port size on the calulator and it should think thats its useing just thicker MDF wouldent it and not mess with anything because the inside of the box is not changing it's always going to be 7

[Davo2378 0]

Thats just what I think if anyone can figger that out.

[Davo2378 0]

what dose everyone else think

[xAndrew225x 8]

Why ask us when you say you think it's fine? Those calcs won't be accurate as bromo said because you're forgetting the displacements. Also the port is too small and will sound like fart.

[altoncustomtech 773]

Why ask us when you say you think it's fine? Those calcs won't be accurate as bromo said because you're forgetting the displacements. Also the port is too small and will sound like fart.

They don't have to be inaccurate if the people who create them think of such things. The calc sheet I use takes, sub,port and port wall displacements into the calculation and with a little ingenuitive figuring anything else such as bracing, plexi, etc. can be added as well. It's not impossible, just takes more time to include.

As far as the OP's design is concerned, I completely agree with Andrew on this. If you think it's fine run with it. It's not enough port area for my tastes either, however I also understand that sometimes a compromise has to be made to get things to work/fit/cooperate in these screwy environments that are our vehicles. I would go through it a few more times, take extra measurements, whatever it takes and be completely satisfied with the theoretical results before making the first cut though, if I were you.

[xAndrew225x 8]

Why ask us when you say you think it's fine? Those calcs won't be accurate as bromo said because you're forgetting the displacements. Also the port is too small and will sound like fart.

They don't have to be inaccurate if the people who create them think of such things. The calc sheet I use takes, sub,port and port wall displacements into the calculation and with a little ingenuitive figuring anything else such as bracing, plexi, etc. can be added as well. It's not impossible, just takes more time to include.

As far as the OP's design is concerned, I completely agree with Andrew on this. If you think it's fine run with it. It's not enough port area for my tastes either, however I also understand that sometimes a compromise has to be made to get things to work/fit/cooperate in these screwy environments that are our vehicles. I would go through it a few more times, take extra measurements, whatever it takes and be completely satisfied with the theoretical results before making the first cut though, if I were you.

When I said calcs, I meant 'calculations' not as in the calculators themselves. My bad lol

If he would insert the bracing and woofer displacement into the calculator itself it would give him a much more accurate tuning and size calculation than what it's telling him at the moment.

[Davo2378 0]

ok so what is the woofer displacements for two sa-15's, because i have no idea what it is

[altoncustomtech 773]

Search function.... two minutes.... easy..... .19cuft per, .38 for two....

[Davo2378 0]

yeah i got it to, and the way the box is right now with the woofer displacements in, the box is tuned to high so I'm going to do something to it, with out making a new one

[sefugi 166]

I would say if the first enclosure is what you are using now, it does not have a good sound because you are tuned a little high. Making the port smaller to acheive a lower tuning would not be the way to go, imo because of the loss of port area.

[Dutchie. 10]

I would say if the first enclosure is what you are using now, it does not have a good sound because you are tuned a little high. Making the port smaller to acheive a lower tuning would not be the way to go, imo because of the loss of port area.

Out of everything I have read, this seems to be your best answer right here.

[zyskatr 0]

Does anyone know what program that is? I'm just getting into enclosure building and need a program...any suggestions would also work.

Thanks!

[brandonf 9]

Does anyone know what program that is? I'm just getting into enclosure building and need a program...any suggestions would also work.

Thanks!

Google chris torres speaker box tuning calculator, all info from looking at the pic

http://lmgtfy.com/?q=chris+torres+speaker+box+tuning+calculator

[RAM_Designs 25]

Definitely tuned too high IMO. Drop it to ~33hz and you'll notice a smoother response with better low-end extension.

Edited March 11, 2011 by RAM_Designs