Enclosure for Two 10"s and One 12"

[dnlpnd]

I have two old sub amps, wiring, and three old subs I'd like to build a custom box for and throw in my daily driver. I have 6 cu ft in my trunk available to donate to the cause.

Previously, the two 4 ohm Lanzar Pro 10's (wired @ 2 ohm mono) maxed out my Hi-Fonics Cyclops and a dual 4 ohm voice coil Kicker Comp VR (wired @ 2 ohm mono) maxed out my Kicker ZR-120.

Using both amps, all three speakers, and single box what would be preferential for either a ported design or a band-pass, them to all to share the same air space or keep the 10's separate from the 12"?

• Ported or Band-pass?
  
• Common air space or separate?
  

Then I also have an old Alpine 7 band parametric that I am wondering if makes sense to throw into the mix upstream of the sub amps. Even though the amps have some low-pass adjustment, the preamp levels and the frequencies to each individual sub amp could be manipulated with the EQ.

Any constructive suggestions would be greatly appreciated.

Thanks,

dnlpnd

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[ashren315]

I don't think it's good to mix sub sizes is it? Doesn't it actually decrease your SPL due to pressure differences created by the different sized subs or something?

 

[garychoffmann 10+ year member]

There is no prefered way to do that. Go ahead and try if you feel differently. Use one or the other. I would do the kicker in 2.25 cubes tuned around 35

 

[dnlpnd]

There is no prefered way to do that. Go ahead and try if you feel differently. Use one or the other. I would do the kicker in 2.25 cubes tuned around 35

Thanks

 

[dnlpnd]

I don't think it's good to mix sub sizes is it? Doesn't it actually decrease your SPL due to pressure differences created by the different sized subs or something?

What pressure difference are you referring to? If the speakers are all in phase and receiving the same signal, you're just simultaneously moving more air...right?

 

[ashren315]

At different levels. You will (likely) get canceled frequencies unless you use extensive crossovers to make the larger subs play like below 40htz and the 10 play above 40htz.

 

[garychoffmann 10+ year member]

What pressure difference are you referring to? If the speakers are all in phase and receiving the same signal, you're just simultaneously moving more air...right?

Not exactly. Everything being equal possibly. More than likely the stroke of the subwoofers would not be 100% in unison thus causing cancelation

 

[dnlpnd]

Not exactly. Everything being equal possibly. More than likely the stroke of the subwoofers would not be 100% in unison thus causing cancelation

So, in the case of a bass-reflex configuration, if the ported/internal side of the 10"s and the 12" were kept isolated from each other (but tuned to the same frequency), you still think there would be cancellation going on in the cabin?

 

[hispls 5,000+ posts]

Mix matching different subs is a terrible idea, sharing an enclosure is even worse.

 

[dnlpnd]

Mix matching different subs is a terrible idea, sharing an enclosure is even worse.

Why is it a terrible idea and if the chambers are kept isolated how is sharing an enclosure any different that two separate ones?

 

[ashren315]

You just get canceling sound waves due to how different sized (or even brand) woofers respond. Just like it's not a good idea to take two identical subs and put one in a sealed and one in a ported enclosure. It changes the way they respond and causes frequency cancelation.

 

[hispls 5,000+ posts]

Why is it a terrible idea and if the chambers are kept isolated how is sharing an enclosure any different that two separate ones?

Mix matching subs or enclosures or anything in a car is inviting trouble, but go ahead and see for yourself.

 

[garychoffmann 10+ year member]

You can isolate the subs and the chambers but you can't isolate the different outputs of both

 

[Jeffdachef 5,000+ posts]

Why is it a terrible idea and if the chambers are kept isolated how is sharing an enclosure any different that two separate ones?

point is they are still both making sound waves and those waves cancel eachother out. Basically they cannot coexist in any way shape or form without you wasting your time and money just to find out a universal truth that is basically common sense in the car audio world. You are 1000x better off selling the 12 and getting another 10 and doing a triple 10 ported or selling the 10s and getting another matching 12 ported.

Also sell both amps and get a proper quality amp thats not hifonics.

 

[loudenuff]

Don't take any harshness as hate. There's a lot of technical **** that goes behind the whole speaker thing, I'd say to even get that close to working you'd probably need higher end subwoofers, a dsp and knowledge on operating it, and a lot of time tuning and trying different types of enclosures. Much more effort than it's worth.