Hypex Scanspeak Dual opposed subwoofer

I have already build a Diy dual opposed subwoofer with 12 inch Scan Speak Discovery drivers and Hypex fa501 amp it sound very good.
The drivers share a 53 liter volume with wool to have a higher Qtc.
But now i have another pair of the same used Scanspeak drivers.
Im planning to build another Dos subwoofer with the bigger fa502 amp 2x500w@4ohm.
Its maybe better to give each woofer his one sealed enclosure with that amp?
In parallel conection with the fa501 amp that was not necessary.
Planning to build the subwoofer 48x50x40cm each woofer has then a seperate 28 liter volume, with wool the Qtc wil be arround 0.78
In that small box the driver can handle all the power from the Fa502 without over excursion i think.
Sombody advise of other thoughts about this project?
 
A image from my first diy project the sub looks like the Arendal 1723 2S
The green line in rew is the diy sub and the red line is a SVS sb2000.
I used 18mm mdf with bracing and wool.

The sealed box for the Hypex FA502 is 8 liter and 2 woofers is also 3 liter less.
The new sub must be bigger to compensate for the bigger amp and have the same netto volume.
But i want not make a bigger box then the Arendal 1723 2S subwoofer
 

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I like sealed and dual opposed, but ported has 10db more output on the tuning freqentie indeed but is way bigger.
With 2 woofers and double the power it plays 6db louder then a single sealed woofer, that is not that far off from the ported version and can also be a smaller box.
Midbase is also 6db louder then the ported with 1 woofer.

I think its best to give each woofer his one sealed enclosure the FA502 is a 2 channel amp.
 
The sub is ready and i make the filters for the dsp.
Red is the SVS SB2000 for comparison.
Green Diy sub flat signal without dsp.
White Diy with dsp 22hz-6db and 16hz-10db
The sub sounds good, it was a nice project!
 

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Recent project sealed sub, driver sees 40 liter qtc is 0.707 for the flattest responce.
Driver Scan-Speak Revelator 32W/4878T00 with Hypex FA 501
Yellow line Diy sub no dsp
Blu Diy with dsp boost
White SVS SB2000 for comparison
In 40 liter the driver behave very well with little dsp.

The sub sounds real good, fast powerfull bass and blends amazing with the mains


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I am of the view that the main advantage of dual opposed subwoofers is the potential for reaction cancelling of driver frame motion. This only occurs if the driver frames are rigidly connected, by a magnet brace or metal rods joining the opposite mounting holes. I don't see how this can happen with each driver in its own sealed enclosure. Maybe I missed something.
 

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@asshatter the Discovery and Revelator drivers have the same moving mass and vas, the Revelater has a bigger coil more xmax and power handeling.
The 1x Rev and 4x Disco drivers blends perfect, but i want to bould the best diy sub also for music and go for their best driver.
A Single Rev with 500w Hypex or a dual Disco with 2x250w Hypex are not that far off @20hz, and the single sub is also a lot smaller.
I look also for a used JL E112 wat is a great sub, but the Revelator diy was way cheaper and i think it also blends better with the Disco drivers.
The Beolab 90 speaker has 10 inch Discos and a single 13 Revelator driver, its a very expensive speaker.
For output are 5 drivers and 2000w Hypex insane, they can move way more air then dual Perlisten D12S subs with THX Dominus rating.
 
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