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

Yes well that is real rosewood veneer, and added about $500 compared to painted MDF. Just don't look too close, it will quickly become apparent these are not at the same level of professional finish detail as say the Audiokinesis Swarm. Not that I couldn't have done that, but everything's a matter of time and effort. This I feel is the right balance for going in my dimly lit listening room.
Rest assured they sound way better than they look!

If you want to see what DIY with freebie cabs can look like, my system is now posted.

I sometimes wonder if the same effect of a DBA setup can be had with way lesser priced subs !?

Yes. For example, Tim has the Audiokinesis Swarm system with one Dayton amp. Read his comments, how awesome it is. Based on his and others info I built my own Swarm using 10" Morel drivers and cabinets from Parts Express. Same size drivers only somewhat higher quality, which is not my opinion, Duke himself told me mine will blow his away. I don't know about that, but they are awesome. Even with real Rosewood veneer and 2 Dayton amps mine came in under $3k.  But based on my experience plus everything I read learning how to build mine I'd say yes you can get remarkably close with much less expensive subs.

I mean your just pressurizing the room right ?

Yes that's pretty much the idea. I'm kicking myself because I noticed this years ago but failed to make the connection. For a while long ago I followed the Home Theater mantra with full range surrounds. The one really positive thing about that was the impressive bass. Which I now understand why. But didn't make the connection back then. Live and learn.

When you think about it in the simplest way the swarm is just 4 passive boxes with a relatively inexpensive 10'' woofer in each one.

 
Right. Parts Express was running a deal when I got mine, free sealed cabinet when you buy the driver. If low cost had been a higher priority mine could have been built for under $2k. In light of how good it performs, that is freaking amazing.

Tim is one who knows what he's talking about, Steve. I don't even need to read his posts any more, they are all so thorough and accurate its only if I have the time any more.

When it comes to which sub, if you have one you like go with it. It does make a difference, obviously a lot of bigger more powerful subs is better than a lot of small weak ones. But try and keep in mind, the number of subs overshadows everything else. In other words I think Tim or I or anyone else with a Swarm type setup will be happy to put it up against any one sub on the market, regardless of price, size, power, or EQ.

My favorite story, which helped me get off my butt and build my DBA, was when Audiokinesis said he had a customer with some enormous budget something like $30k just for subs. Dude went and compared a lot in that price range, wound up buying a Swarm for 1/10th and not because it was cheaper but because it was better.
Now honestly if it was me I would have bought four or five better subs, heck with that kind of money make it six or seven. What I would NOT ever do is pour big money into only one or two, or even three. The improvement from more subs that far overshadows the improvement from anything else.
Hard to believe, I know. That's why Tim and I keep hammering on it.

Very risky scm taking advice from one of the least knowledgeable on this subject on the whole site. DYODD.

The Audiokinesis Swarm are ported, yes, but all come with plugs. Plug a port and it becomes a sealed speaker.

There's nothing magical about ported/sealed. Its simply a tradeoff made between efficiency, extension, and cabinet volume. Briefly, ported speakers tend to have a response curve that is more efficient at higher bass frequencies, but then falls off rapidly past a certain point, the tuning frequency. Sealed cabinets have a lower efficiency but fall off more gradually. So plugging a port has the effect of reducing bass output at what tends to be a more problematic range due to room reinforcement, while also allowing a little deeper bass thanks to the more gradual rolloff. 

Two of my 5 subs are sealed. Two are ported. One, Talon Roc, is isobaric and ported. Isobaric is when two drivers are mounted together such that they both move the same air together. Anyway, point is, it is perfectly okay to mix. Often times in fact it is preferable. 

Watch who you take advice from around here. Remember, there's no editors, and anyone can post.