So It`s Ok To Mix and Match Ported and Sealed Subwoofers ??

Update !

I decided to just  add two more subs.
I bought a pair of HSU ULS-15 mk2`s they are on their way from HSU right now.
They are a satin black..to get the Rosewood finish like Chucks it would have been an additional $300 or so unfortunately :(
They are supposed to be a very musical sub from all that I read and that was a huge part of my final decision making.

So I`ll have my 15" Revel sub plus the two HSU 15" `s and a 10" powered sub all sealed versions.
I`m hoping the subs will do well enough in my 3800 cu ft room....will see 

Hello scm,

     Excellent, from what I've read, the HSU ULS-15 mk2 are a very good choice.
    I suggest you first setup and audition a custom 3-sub DBA system in your room, using your 15" Revel/with Dayton amp and your 2 15" HSU mk2 self-amplified subs.  
     It's important to position each sub optimally in your room.  I think using the crawl method, starting your search at the right front corner of your room and moving counter-clockwise around the perimeter of your room, should be sufficient for positioning each sub but you're welcome to use a more sophisticated method if you have the equipment and know how to use it.
     Once all 3 subs have been optimally positioned, proper setting of each sub's volume, crossover frequency and phase controls are the next critical steps.  Ideally, your goal is to have the volume of the subs match the volume of your main speakers and resist the urge to turn their volume up too high, you only want the subs to be active when the musical content demands it.  I've found it useful to set the volume as low as possible with the bass still sounding powerful, dynamic, detailed and natural.
     For the cutoff frequency settings, I suggest running your main speakers full-range and initially setting this control on each sub at about the rated bass extension frequency limit of your main speakers.  You can then adjust this setting slightly upward and downward until each sub is perceived as seamlessly integrated with your main speakers. 
    For the phase settings, I suggest you initially just set each to the position the bass sounds best to you.  I don't think this setting is as critical as the other 2 but I can detail more precise methods of optimally setting the phase on each sub if you'd like.
     I'm more than willing to further assist you when your new subs arrive if you'd like.  Just let me know on this thread or PM me.

Tim

Tim..that looks like a good plan to me !
Thanks Again   
Steve

Excellent, from what I've read, the HSU ULS-15 mk2 are a very good choice.

They are very good. :) Monsters in fact.

Hello Steve,

     Okay, good.  You should be aware that I went from 2 subs to 4 subs in my system search for high quality bass.  I've never tried 3 subs but one of the most prolific acoustic researchers and advocates of the 4-sub DBA concept, Dr. Earl Geddes, has stated that 3-sub DBAs can be as effective as 4-sub DBAs if the 3 subs are properly positioned and configured, with configured meaning the volume, crossover frequency and phase controls are optimally set.
     I have no reason to doubt that 3 subs can work well but I can't help thinking that optimum positioning of each sub is likely more important when 3 subs are used than when 4 subs are used.  I have complete confidence in the crawl method of sequentially positioning each sub in a room, since I've used it effectively in my room with 2 and 4 subs, but wanted to make sure you're aware of exactly how to do this.
     I'm also thinking that you have the option of creating a custom 4-sub DBA system, by including your smaller 10" self-amplified sub as the 4th sub, if you'd like.  In other words, your room is large enough that I'm fairly certain that 3 large subs will provide high quality bass throughout your entire room, if precisely positioned and configured, but I'm very close to certain that 3 large subs and a 4th smaller sub will do so.
     I still  think a good plan is to setup a 3-sub DBA system, closely evaluate the results for a few weeks and progress to setting up a 4-sub DBA system only if you're not completely satisfied with the 3-sub DBA system results.


Later,
Tim