sealed/ported convertible subwoofer

Looking at the L26ROYs distortion... damn that's impressive! Really puts the SDX10 to shame.

I tried modelling 1x L26ROY in a 1.6 cu ft sealed enclosure. I get a QTC of 0.613. F3 46hz F10 24hz. It exceed excursion but works with a high pass at 20hz. SPL is at 108db with 200w.

Would that work? It's at the max end of my budget.

I'm just worried the L26roy wasn't intended for sealed sub... when I run it in WINISD, the program tries to suggest a ported enclosure LOL
 
german loudspeaker building magazine "hobby hifi" tested RSS315HF in 2011 (link to tested drivers overview).
I don't have that exact issue, but i read tests of RSS210HO-4 and RSS390HF-4 and both are told to have excellent distortion numbers (RSS210 even up to midrange).
I found some measurements of the Rss315hf by John marsh, and same thing. The distortion performance is excellent. The rss315 just models better than any 10" I tried in a sealed enclosure. I think it makes the most sense to just stick with a 12 inch Dayton build.
 
I'm in the middle of coming up with sub dimensions, and it's going to be tight. Pretty much 1/8th of an inch on either side of the flange. I will be routing the outer inset hole very close to the edge.

The internal width will pretty much be the exact 282mm, where the flange meets the basket/frame. I was going to rotate it so that 2 of the metal supports of the frame will be adjacent to the side walls of the cabinet. Like in the picture below. I'm hoping that would allow the woofer to breathe.

Does anyone see an issue with doing this?

sub cabinet.png
 

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I built a convertible box just like you are planning. I used metal pipe plugs with a rubber gasket inside that expands when you turn a wing nut on top. They work awesome, no vibrations or leakage. Just needed 2 because they're only 4 inch I believe. Also, for what it's worth I never remove the plugs. The sealed enclosure on the large size is very noticeably more accurate, even when both are room corrected. Transients are more crisp. Extra spl with vented is not worth the tradeoff, and I'm blinking distortion lights on 800 watt amps regularly so I do crave huge output.
 
I built a convertible box just like you are planning. I used metal pipe plugs with a rubber gasket inside that expands when you turn a wing nut on top. They work awesome, no vibrations or leakage. Just needed 2 because they're only 4 inch I believe. Also, for what it's worth I never remove the plugs. The sealed enclosure on the large size is very noticeably more accurate, even when both are room corrected. Transients are more crisp. Extra spl with vented is not worth the tradeoff, and I'm blinking distortion lights on 800 watt amps regularly so I do crave huge output.
Thanks for the response. The more I read, the more I decided I would be happiest with a sealed sub.

So I pretty much scrapped the idea of doing the convertible. That way I could optimize for a sealed enclosure, rather than try to compromise and use a port too small etc. It's why I had to go for a 12" driver, since I figured the extra Vd is necessary when going sealed...

Amazing how much you learn just playing with winISD.
 
If you care most about a good clean impulse response - punch - then build a sealed box. You can reach lower with a ported box, but you might have a lack-of-space problem.

If you find a design that looks like it will sound good but it has an infeasibly large port volume, you can sometimes fix that by using a passive radiator. The PR is a non-driven cone with mass added, which behaves like the moving mass of air in a port. The cost a bit of money - though less than a driver - but can often allow you to build a much smaller "ported" box which is tuned really low without needing to use a huge volume. And they're easy to tune by adding/removing mass, equivalent to changing port length.