2 - 15" or 4-12" ??

[Papermaker85 5,000+ posts]

you guys are arguing over cone area instead of displacement, power compression, efficiency power avible and box design.

i've use the AQ woofers they are decent woofers.

no one can tell you for sure exactly what would be better without know jack **** about the box design potential cancellation and phasing issues among several factors that will make a difference. SMH

 

[Jeffdachef 5,000+ posts]

are most 4th 2-1 ?i take that as 2 ( sealed ) ( 1 ported ) ?

go 3 to 1 if possible, output gain is quite a bit more vs just a 2 to 1 or 2.5 to 1. Use poly fill in the sealed as needed if space is an issue and invert the woofers to be in the ported section.

As for the port tuning, you want to build the sealed section first and try to get your sealed section resonating around 45-50hz with the sealed design and test the subs to see what your cabin peak is at by playing a sweep and measuring it on the termlab and tune your ported section around that frequency (usually 47-52)to get maximal output. Keep in mind its vehicle dependant, these are just good starting points.

Port area is determined by 1/2 cone area and no not the 6 x 6 x 3.14 calculations. You want to use the actual SD figures from the TS parameters or actually measure out the sub properly with a ruler from peak surround to the other peak surround. Generally can use a lot less port area with a more efficient port such as a square, octo or aero/round sonotube port. You can also easily change tuning as needed with those types of port much easier than slot by adding or removing length. Will take several experiments and testing to get optimum painful slammage.

 

[jordon]

A 4th order for 4 12s would be a big box would it not?

 

[germanyt 10+ year member]

A 4th order for 4 12s would be a big box would it not?

They aren't small.

 

[Papermaker85 5,000+ posts]

edit.. what does that setup hit?

 

[Jeffdachef 5,000+ posts]

A 4th order for 4 12s would be a big box would it not?

looking right around 20 cubes gross for a 3:1. Thats not counting extra thickness.

 

[Papermaker85 5,000+ posts]

i dont understand why you need such a huge box. you could do 10 12s in that air space and it would be a no contest..

 

[Jeffdachef 5,000+ posts]

i dont understand why you need such a huge box. you could do 10 12s in that air space and it would be a no contest..

4 subs in a large ratio are going to be much more efficient than 8 subs in a small ratio. Now, if you have 100,000 watts on tap, you may just need to go with more subs just to split up the power some, but we are going to assume you have a reasonable amount of power...lol. But a 3:1 is a good starting point for the typical ground pounder, if you want higher SPL, you can even go 4:1 or even 5:1 if you have the room. As far as efficiency goes, in comparing a 1:1 to a 3:1 is about a 3dB gain(before cabin gain) with the 3:1, and a 3:1 is about 1.5 dB louder than a 2:1, which equates to about the same as 50% more cone area or 50% more power...

Thats why you see guys with 10 : 1 ratios making mad SPL numbers in the lanes with a lot less woofers and power than the rest of the competition.

You also talk if he's willing to shell out 1000 dollars for ten 12s and the amount of power you need to push it along with electrical upgrades. People arent walking banks bro.

 

[Popwarhomie 5,000+ posts]

My buddy was doing 158s with 4 zv4 12s in a 4th order blow through. I have videos on my YouTube.

Nic watts does 160s with 4 12" 4th blow through. He lives pretty close to me. Truck is nasty!

 

[Papermaker85 5,000+ posts]

why not do 6 12s ported? 4th order only uses one wave. if your gonna go through all that trouble why not and transmission line or a wave guide?

the higher the ratio the peakier the woofers will be like varying the ports surface area and loading the port by using a much less internal airspace. your basically compound loading the driver(a similar effect as bandpasss which IS compound loading) and using the port to increase displacement. the biggest thing with a ported box is getting the rear wave correct. wish i still had pics of the wave guide i done for my dad. although you can never get all the the bandwidths frequencies in perfect phase its still much more efficient that a typical ported box thats typically 5-60 degrees out of phase.. im not saying they **** or they aren't good i just think its such waste use just the front wave when a good driver can be ported and using the 1/4 length waveform wave guild gives you HUGE efficiency gains.

 

[Papermaker85 5,000+ posts]

My buddy was doing 158s with 4 zv4 12s in a 4th order blow through. I have videos on my YouTube.
Nic watts does 160s with 4 12" 4th blow through. He lives pretty close to me. Truck is nasty!

how much power? friend had 6 ED E 12s off 2 JBL 1200.1s doing 156 and it was pretty **** flat.. that was some 140$ drivers and some 250$ amps..

 

[sinzx2]

Lol I hope this is a joke.

my bad, 2 15" = 353"

4 12" = 452"

the point still stands, all things being equal in properly tuned boxes the 12's should be louder

 

[lovinloudbass 10+ year member]

The larger the ratio the peekier it will be across a bandwith. With a lower ratio u will flatten out the response but will give up db's, best bet is to find someone that has experiance designing and tuning 4th orders. They are not that **** easy to get right.... Drunk post fyi

 

[Popwarhomie 5,000+ posts]

how much power? friend had 6 ED E 12s off 2 JBL 1200.1s doing 156 and it was pretty **** flat.. that was some 140$ drivers and some 250$ amps..

Taramps 20k. Never clamped power though.

Nic watts runs 4 twisted sounds 8.5ks on 4 nightshade 12s.

 

[els1989]

probably the 12's because of more cone area 30" vs 48"

Ahem it's approximately 452sq in=4 12's and 353sq in= 2 15's

I see you already corrected yourself lol my bad

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