Small or large sub for music

noble100
Yeah, my daisy chain remark was directed to the original poster dbphd but I failed to make that point in both of my posts. 
I then confused your use of the Dayton Sub amplifier and High level conectivity with dbphd's HGS subs.

In the word of Rosan Rosanna Danna, "Never mind"! 

ejr1953
When I did a half baked subwoofer comparison between my Velodyne DD-18 with two other sub owners of a REL Studio III and a JL Audio Fathom F113 (v1) using the JL Audio ARO there was a slight but audible peak just below the main speakers crossover point.

This was clearly visible using the Velodyne Room Optimization program. I was able to dial some of it out using the F113s LP freq. (Hz) dial. Bypassing ARO and using the Velodyne Manual Optimization I was not only able to clean up the crossover point make some Q adjustments and cut and boost a few other places to really smooth out its response and improve the F113s overall performance.

I understand JL Audio has made improvements with their v2 and is also marketing an ancillary companion crossover component. Regardless, the JL Audio is a very fine system that provided nearly the same girth of output of the DD-18 that seriously belies its 13" drivers size.    

   The Swarm and Debra subs are 'vented enclosure for correct roll-off to compensate for room gain (ports can be plugged with supplied plugs, if desired)'. I've tried my Debra subs both ways and preferred them unplugged.

The Swarm and Debra subs are an excellent example of using science and good acoustic theory to maximize the benefit for the minimum dollar.  They have addressed the biggest issue, the room.  It can be done with any 4 subs.  You should see what some of the crazy home theater guys do, as the Swarm would never have enough deep bass for them (they want 120db @10 hz), things like quad JTR Captivators.  Not to plug another forum, but AVSforums in the subwoofer section has some really great information on setup, tuning, and objective reviewing.  The home theater guys have done more for good bass than just about anyone.  

"More important, IMO, is to have a SEALED sub for music."

Can anyone provide a supportable reason for this, or is this just an ad nauseum repeating of inaccurate information?  

It's a myth, with a completely different issue coming on. Sealed have higher f3, and fewer problems with the room. If you know what you are doing you can make a ported sub work fantastically. If you don't, get a sealed 10" sub and leave it alone. :)