cu ft on a box...

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there one thing i cant find any info on

for exemple i have 2 pioneer ts-w308d2 in my case i have single box spilt at the midle 1.9 cu ft each chamber....

if i have done one box for 2 subs just one big chamber not split, i would have to had up 1.9+1.9 cu ft from each sub required cu ft space and have a 3.8 cu ft box for the subs and each sub see 1.9 cu ft or each sub will see just the big 3.8 cu ft box ?

and the port? add up and dooble the port size or keep the same size, if keep the same port the box tunewill be the same (+/-34hz) or change? and will have air shuffle noise?

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[BOOMINGRANDPA 5,000+ posts]

there one thing i cant find any info on
for exemple i have 2 pioneer ts-w308d2 in my case i have single box spilt at the midle 1.9 cu ft each chamber....

if i have done one box for 2 subs just one big chamber not split, i would have to had up 1.9+1.9 cu ft from each sub required cu ft space and have a 3.8 cu ft box for the subs and each sub see 1.9 cu ft or each sub will see just the big 3.8 cu ft box ?

and the port? add up and dooble the port size or keep the same size, if keep the same port the box tunewill be the same (+/-34hz) or change? and will have air shuffle noise?

no it's the same 1.9cf either way.. yes if u do shared chamber box u could use same size ports but with your 1k crossfire i would say subs would be better and have less chance of bottoming out with 1.7cf per sub so 3.4 or so cf shared box...... also the smaller the box the less port noise u would have with same port size but if u use same port length it would tune higher with smaller box so if u want to stay same tuning port would have to be a tad longer.. and u could just do 1 bigger port or slot port out of wood like mine.. if u look in my gallery u will see the dual 3.2 cf box i had for pioneer subs in that pic it had black elemental design subs in it..

 

[honkyg 10+ year member]

our atmospheric air is a compressible fluid, so it has inherent opposable springiness upon compression.

ive learned that in terms of loading, taking drafted specs from a single driver bass reflex and applying it to a double driver enclosure keeps the imp rise and loading equal when you situate the port center for equidistant propagation. its not louder, but more accurate and helps when using more than one amp.

the issue ive come across is that port velocity and pressure are augmented when combined from double to single port as internal port surface area per cubic increment of air flowing, thus port compliance.

 

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for now i´m happy with my box, not thinking about changing but that was a doubt in my mind....

about my box beeing 1.9+1.9 cf, total 3.8 cf, pioneer says 1.65 cf recomended and 2.05 cf max per sub... i think i made the right choice to build closer to the bigger...

 

[THATpurpleKUSH 5,000+ posts]

Dividing the volume of the box by the number of subs used is generally a safe practice. 3.8cf / 2 subs = 1.9 per sub

You can double the port area but keep in mind the length will change and will need to be shorter to keep the same tuning because port tune isn't a linear function.

 

[BOOMINGRANDPA 5,000+ posts]

for now i´m happy with my box, not thinking about changing but that was a doubt in my mind....
about my box beeing 1.9+1.9 cf, total 3.8 cf, pioneer says 1.65 cf recomended and 2.05 cf max per sub... i think i made the right choice to build closer to the bigger...

i will tell u i went from 1.8cf to 1.6 cf on my 3003 pioneer and it sounded better/ louder.. here a easy port calc, in case u change box use this to see how long ports or port should be.. Port Length Calculator

 

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i will tell u i went from 1.8cf to 1.6 cf on my 3003 pioneer and it sounded better/ louder.. here a easy port calc, in case u change box use this to see how long ports or port should be.. Port Length Calculator

i buy this subs used and they came on that prefab boxes a sloted ported box about 3cf total and after change to this box i gain like 30% more bass

 

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maybe some day i sell this pioneers in the box and change to a single 12" or even a 15" but something like 800 to 1000 rms

what do u guys think it would be bether than my 2 400 rms 12" pioneers?

 

[BOOMINGRANDPA 5,000+ posts]

i buy this subs used and they came on that prefab boxes a sloted ported box about 3cf total and after change to this box i gain like 30% more bass

that was probaly mostly because of port tuning though..

 

[BOOMINGRANDPA 5,000+ posts]

maybe some day i sell this pioneers in the box and change to a single 12" or even a 15" but something like 800 to 1000 rms
what do u guys think it would be bether than my 2 400 rms 12" pioneers?

1 12 or 15 with bigger motor, more excursion more power to it can be louder than 2-12's with 1/2 the power yes but that depends on what u can find.. don't u have lot more bass now with bigger amp?

 

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1 12 or 15 with bigger motor, more excursion more power to it can be louder than 2-12's with 1/2 the power yes but that depends on what u can find.. don't u have lot more bass now with bigger amp?

hell yes, but still have to tune everything to "100%" i just set up everything to have bass... im making some upgrades/changings at the sistem tomorow i will post some pics at my instal post

the part of maybe one day change to 1 12 or 15 (probably a 12) is for exemple if one pioneer die or if i need trunk space or if a get tired of havving the same sistem with the 2 12...