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The long standing debate is sealed vs ported. And the answer usually boils down to: Whichever one you prefer the sound of.

I am just curious what kind of results I would get if I put a 12 in a ported box and had two 8's flanking it in their own sealed boxes. Obviously, I could mess with the crossover points and let the 8's play at frequencies above the 12, but I am more curious about if they all played the same range. Would the two box types play well together or would I likely end up with a messy combination of soundwaves fighting each other?

Thanks.
 

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You are probably better off putting the money into decent MB drivers, and choosing a sub enclosure that plays well into the bottom range of the mid base.
Maybe you are better off with a bandpass?
 

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The long standing debate is sealed vs ported. And the answer usually boils down to: Whichever one you prefer the sound of.

I am just curious what kind of results I would get if I put a 12 in a ported box and had two 8's flanking it in their own sealed boxes. Obviously, I could mess with the crossover points and let the 8's play at frequencies above the 12, but I am more curious about if they all played the same range. Would the two box types play well together or would I likely end up with a messy combination of soundwaves fighting each other?

Thanks.
Seems you'd need a lot more eq/processing and effort to fix said messy combination than to fix the response of either subwoofer system alone.
 

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Actually, I always played with the idea of having a pair of sealed dubs and a ported in a unique enclosure and just toggling a 3-way switch to select which I wanted playing, depending on my mood and music at the time. That was about 15 years ago, before I knew anything about tuning a system (not that I know all that much now).

I'd like to think you could set up a DSP with a couple tunes you could switch between on the fly (more or less).
 

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Actually, I always played with the idea of having a pair of sealed dubs and a ported in a unique enclosure and just toggling a 3-way switch to select which I wanted playing, depending on my mood and music at the time. That was about 15 years ago, before I knew anything about tuning a system (not that I know all that much now).

I'd like to think you could set up a DSP with a couple tunes you could switch between on the fly (more or less).
Another thing I’ve done on the home theater side for a professional home theater designer was use All-pass filters to align the phase of sealed and ported subs. Wouldn’t be easy but could be an option to play both together.

Or use your idea for a DSP present that mutes one or the other.
 

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Discussion Starter #8
So it seems my suspicion of the two styles of boxes fighting each other (so to speak) has been somewhat substantiated.

Thanks guys.
 

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Years ago, I did exactly this. I had 2 15's in an isobaric enclosure, flanked by 2 8's in sealed boxes. Back then it was more for aesthetics than anything else, and long before DSP's were readily available. My memory was that it didn't sound bad, but then again, the 8's were in the trunk, facing the rear, and the 15's SLIGHTLY overshadowed them! lol
Man, this was some cheap ass gear I had back then. DHD powercruiser 15's, and DHD 8's, All DHD amps, and an Audiobahn 30 band eq.
 

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So it seems my suspicion of the two styles of boxes fighting each other (so to speak) has been somewhat substantiated.

Thanks guys.
Definitely different phase characteristics because you’re getting direct-radiated waves from the cone and sound waves through the port. Those have to be aligned plus the direct-radiating waves from a sealed subwoofer. It can be done with a good DSP where you put the ported on one DSP channel and the sealed on another but it won’t necessarily be easy.
 

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So it seems my suspicion of the two styles of boxes fighting each other (so to speak) has been somewhat substantiated.

Thanks guys.
It seems like goal was something for one band, and smaller subwoofers for another band. With two DSP channels one could do that.

It seems easier to just use a bandpass box.

What ranges would sub1 and sub2 play? If they are the same range, then what are they doing different...
What exactly is the goal, and do two get to that goal?

As my grand father use to say, two wrongs do not make a right, and 3,4 or 100 also do not.
A single better approach may be good?
 

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Definitely different phase characteristics because you’re getting direct-radiated waves from the cone and sound waves through the port. Those have to be aligned plus the direct-radiating waves from a sealed subwoofer. It can be done with a good DSP where you put the ported on one DSP channel and the sealed on another but it won’t necessarily be easy.
But people seem to forget that at the crossover point the port would be doing nothing if you got the crossovers well placed (say a 25hz tune and a 50hz crossover) as at that point the ported enclosures phase would then effectively be like that of a sealed box and it would be no harder than matching 6” midbass to a ported subwoofer, levels, phase and time alignment would have to be bang on but that’s no different to guys that run a front sub and also a rear sub as well

For example tonny Evers in EMMA uses a ten (150hz all the way down) in the centre of his dash to compliment a 15 in the boot (both are sealed but see my above about port tuning vs crossover)

So in effect it can be done and unlike the old days when we had zero control other than phase generally we have lots more tools at our disposal

I’d be willing to bet a lot of myths are more the basis of the ‘don’t do it’ brigade than crack on, years ago you wouldn’t have dreamt of putting 10’s in kicks or similar, yet you could put tens in kicks and run an 18” ported for sq nowadays and it works

As above (sorry the guy I’m quoting, it’s not aimed at you!), I’m not saying it would be easy, but with the correct implementation I don’t see why you couldn’t
 

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Why would you push different drivers to play the same part of spectre?
IMHO it is better to advantage each driver for its own part of spectre with coresponding X-Overs...less chances for phasing, cancelation issues, and why would you pyt smaller driver to the strees to play the lowest frequencies and introduce additional distortion to the sound.

Also a different roll off characteristic of different enclosures can be a problem too....for now IM JUST LOOKING AT WHY NOT TO DO SUCH THINGS, But if we never try we will for ever hang on only why not excuses,....the fact is like DumDum sayd - now we have a lot more tools to bring things together that we could not even dreamed about 10 or 20 years ago
 
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