Second Voice Coil For Bass Boost

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Specifically speaking about this woofer;
Aurum Cantus AC-180F1D

But....generally speaking, I understand about using a .5 woofer in full range speakers.

How about having a small sealed DVC woofer like the one above.
Then placing an inductor in series to the second voice coil restricting it's response to say.....50hz and below.
I know the choke will be huge, but, technically speaking would it enable you to have lower response in the same size sealed enclosure at the expense of straight up sensitivity V.S. having the 2 voice coils in parallel?
 
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I had that thought as well.
However, if the natural F3 sealed of a single VC is 70hz and you add in the second VC at 1/2 octave below that around 50hz or so then a 6db LP slope combining with the 6db HP slope should create a flatter response around 70hz.
Then the additive boost at 50ish should hold the F3 out a bit more at the sacrifice of the 3db overall sensitivity of both VC's in parallel.....
Maybe I'm missing something....?
 
Nice thought experiment. Seems easy enough to implement. Some accuracy is sacrificed however it's hard to say if it would really sound bad or not. "Good" is incredibly subjective, especially with bass reproduction. Given the desire for small volume enclosure it might be worth the trade off. In the interest of exploration, I say push forward if you like experimenting.

fwiw, there are many cabinet geometries that people enjoy which mangle the phase at least as badly as what you're proposing.
 
Short answer: it won´t do what you want.

It won+t "go lower" by any means: 2 boxes same size, same speakers, will sound the same, have same resonant frequency, rolloff the same, just will sound louder (but at same frequencies as before) because of acoustic cross coupling and plain old pulling more power out of your amp simply because halved impedance.

"Cheating" by making the crossover frequency lower than the rolloff point won´t help much, if at all , because you are helping a weakened speaker (at that lower frequency) with another equally weakened speaker, so ....

There was an old proverb about "the blind leading the blind" .... some variation might apply here.

If anything, try putting your original speaker inside a doubled volume cabinet and see where that leads you.

After all, you *already* accepted a second cabinet.
 
Jared, look up the Sonus Faber Extrema version 2. That has an active coil PR with resistance across it.

As to the X.5 method with a DVC driver, Focal used to have kits like that in a 2-way. In terms of subwoofers, you'd get the +6dB below the Fc of the coil, just like in BSC, where the bass range halves the impedance. However, the Fc of the coil if low enough can cause an additional boost in combo with the driver's Fs. You might even get more output than expected, but the DVC will still only have the same Fs and Mms. It's likely more output can be put in a certain range if required, but actually going lower really can't be done unless changing the box or trying the 3rd order sealed response, or going with active means of some sort.

Later,
Wolf
 
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