Air space

[Mr FaceCaser]

So I'm about to buy a box for 2 of the sundown uv2 12" subs and I got recommended a box by a very good person but the bix only has 3.25 cubic feet of air space the subs call for 2 for each so 4 total I was trying to understand why I don't need the full 4? I totally trust what he recommended as he knows 10000% more then I do but I was just curious why

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[SlugButter]

So I'm about to buy a box for 2 of the sundown uv2 12" subs and I got recommended a box by a very good person but the bix only has 3.25 cubic feet of air space the subs call for 2 for each so 4 total I was trying to understand why I don't need the full 4? I totally trust what he recommended as he knows 10000% more then I do but I was just curious why

That seems a little short, but it depends on your music tastes and the amp power you’re running, to a degree. What are your music tastes? Are you going to run test tones and meter your system on a ton of amp power?

 

[Mr FaceCaser]

That seems a little short, but it depends on your music tastes and the amp power you’re running, to a degree. What are your music tastes? Are you going to run test tones and meter your system on a ton of amp power?

I like all types of music but mainly rap/hip hop and r&b. No metering and test tones yet. Them amp is 3500 @1 ohm and I have the subs wired parallel/parallel to equal 1 ohm

 

[chillin 10+ year member]

Are you looking at a sealed or ported box? They only need 1 cube each sealed.

 

[Buck 5,000+ posts]

I like all types of music but mainly rap/hip hop and r&b. No metering and test tones yet. Them amp is 3500 @1 ohm and I have the subs wired parallel/parallel to equal 1 ohm

I would do what Sundown recommends.

 

[Mr FaceCaser]

Are you looking at a sealed or ported box? They only need 1 cube each sealed.

Ported

 

[Mr FaceCaser]

I would do what Sundown recommends.

Okay

 

[Doxquzme Premium Member]

I saw that too. It was an oversight I believe or that was the net volume after woofer and ort displacement. GP audio actually sells those subs and they recommend the 2.0 cu ft per sub as well. I've not been able to find if that is pre-woofer/port/brace displacement or not. I would call sundown tomorrow and find out if the recommended 2ft per sub is net or gross. I'm thinking that you may actually need the 4.5 cu ft box after woofer and [port displacement is figured in. Worth a ten minute call before you hit the $$ (buy) button!

 

[Mr FaceCaser]

I saw that too. It was an oversight I believe or that was the net volume after woofer and ort displacement. GP audio actually sells those subs and they recommend the 2.0 cu ft per sub as well. I've not been able to find if that is pre-woofer/port/brace displacement or not. I would call sundown tomorrow and find out if the recommended 2ft per sub is net or gross. I'm thinking that you may actually need the 4.5 cu ft box after woofer and [port displacement is figured in. Worth a ten minute call before you hit the $$ (buy) button!

True I'm gonna email them to. What's the difference in net and gross?

 

[SlugButter]

Advertising net volume always bothered me. When you put subs in a box advertised at 2 cubes and lose .25 cubes of air space you not only lose the air space, it also raises port tuning. What you thought was 2 cubes @ 32 HZ is now 1.75 @ 35 HZ.

 

[Mr FaceCaser]

Advertising net volume always bothered me. When you put subs in a box advertised at 2 cubes and lose .25 cubes of air space you not only lose the air space, it also raises port tuning. What you thought was 2 cubes @ 32 HZ is now 1.75 @ 35 HZ.

Okay makes sense so if it's net get a lower tuned box so it matches up with the recommended tuning but if it's gross just do the 4 cubic feet with 35 hz tuning ( I have 2 subs btw trying to fit into a 2012 nissan altima sr)

 

[Doxquzme Premium Member]

Vb or the net internal volume of the box or chamber. This is the volume that remains after subtracting the volume inside the box that is displaced by internal objects like the driver, vent and bracing. Gross would be for volume prior to the driver displacement, port displacement. Think of it in terms of your paycheck. Gross is prior to taxes, Insurance, 401k, etc. Net is after they take stuff out of the equation (paycheck) that you are left with.

Just call and ask what the Box VB (or net volume) is, if it is 2 cubes per driver, then that 4.5 cu ft box will be your ticket. Might as well ask them what the driver displacement is too. I'm guessing between .2 and .25 cubic ft. Once you get that info, we can look at the correct box configuration that GP offers to suit your tuning needs..

 

[Mr FaceCaser]

Vb or the net internal volume of the box or chamber. This is the volume that remains after subtracting the volume inside the box that is displaced by internal objects like the driver, vent and bracing. Gross would be for volume prior to the driver displacement, port displacement. Think of it in terms of your paycheck. Gross is prior to taxes, Insurance, 401k, etc. Net is after they take stuff out of the equation (paycheck) that you are left with.

Just call and ask what the Box VB (or net volume) is, if it is 2 cubes per driver, then that 4.5 cu ft box will be your ticket. Might as well ask them what the driver displacement is too. I'm guessing between .2 and .25 cubic ft. Once you get that info, we can look at the correct box configuration that GP offers to suit your tuning needs..

On the website says driver displacement is .21 I know that and so the 4.5 cubic foot box won't fit in my car but the 4 cubic foot box will bc I can drop the width from 38" to 34" and raise the height to 18" ( I hate having a small car wish my Ford explorer never got totaled)

 

[Doxquzme Premium Member]

On the website says driver displacement is .21 I know that and so the 4.5 cubic foot box won't fit in my car but the 4 cubic foot box will bc I can drop the width from 38" to 34" and raise the height to 18" ( I hate having a small car wish my Ford explorer never got totaled)

Do you have enough room to invert the drivers?

 

[Mr FaceCaser]

Do you have enough room to invert the drivers?

No sadly not my trunk is only 19.71 inches tall.