Does inner cabin volume determine box

[carshateme]

Okay...a while back a guy I talked to who was an audiophile said if you have a small inner cabin space...your subs would want to be sealed...and big inner cabin space would be ported..

Only reason I'm asking this question is because I have a Buick Skylark...the inner cabin isn't really that big and I'm deciding on either to build a ported box...or keep the sealed box that I have now. Thank you.

[SQMonte]

Cabin size surely factors in to the equation, not necessarily for what type of box to use but surely to plot out the response of said enclosure. The TS specs of the sub determines what enclosure it would be better suited for.

[teardrop]

what he said ^^^^^

[carshateme]

Cabin size surely factors in to the equation, not necessarily for what type of box to use but surely to plot out the response of said enclosure. The TS specs of the sub determines what enclosure it would be better suited for.

So what would you suggest for a sub that has

Qts: .47

Qes: .51

Qms: 4.9

Vas: 35L

Vas: 1.24ft^3

???

[baaudio]

Fs vas and qts are important factors from my understanding. Qts of .4 or less ported and .5 or more sealed

[carshateme]

Well in my manual ...for my subwoofers...it says something like and EBP of less than 45 is for sealed...and greater than 65 for a ported box...although the EBP of my subs are 56...so that's what I'm confused on.

[Bump4life]

What type of Subs are they?

[SQMonte]

Well in my manual ...for my subwoofers...it says something like and EBP of less than 45 is for sealed...and greater than 65 for a ported box...although the EBP of my subs are 56...so that's what I'm confused on.

I'm no pro, but it seems to me they can be used equally well in either. Generally, ported boxes will be louder, but sealed will allow better power handling. Sealed boxes can hit just as low as ported too.

[Joe X]

You have 2 different issues that you should not confuse:

1) what enclosure is better for a particular sub.

2) what type of enclosure is better for a particular cabin

For question 1 you calculate the following as a general rule:

EBP = Fs/Qes

<50 sealed.

>100 Ported.

between 50 and 100 you could use in either.

For question 2 sealed will usually give you better transient response and lower group delay plus this:

Since sealed has a roll-off of 12dB/octave and cabin gain raises at 12db/Octave starting at 50-90Hz you can get to cancel each other giving you a perfectly flat low frequency response. So properly used sealed is best for SQ. If your cabin is huge you can't get that and then ported is the better way to get bass.

[Bump4life]

You have 2 different issues that you should not confuse:

1) what enclosure is better for a particular sub.

2) what type of enclosure is better for a particular cabin

For question 1 you calculate the following as a general rule:

EBP = Fs/Qes

<50 sealed.

>100 Ported.

between 50 and 100 you could use in either.

For question 2 sealed will usually give you better transient response and lower group delay plus this:

Since sealed has a roll-off of 12dB/octave and cabin gain raises at 12db/Octave starting at 50-90Hz you can get to cancel each other giving you a perfectly flat low frequency response. So properly used sealed is best for SQ. If your cabin is huge you can't get that and then ported is the better way to get bass.

What he said ^^

Most of the time SQ= sealed. SPL=ported. But if your good with ported boxes and you have room just make a huge box and tune very very low and you will have plenty of SQ.