Axiom Home Page Forums General Discussion Home Theater FWIW

I got the first ported one because I had a large CuFt space to fill, could only buy 1 sub, and needed a lot of LFE power for my $850 that I spent. The port gives you that for large spaces like that.

I then added a "twin performing" DIY sub to try to keep things identical. That smoothed out the room nodes a decent amount, and also meant that I could run both of them at a lower gain than one alone, meaning less air pushing and pulling through the port.

Sealed subs or much more musical of course, and can give a tight "punch to the chest" feel, which is why I am wondering if adding a 3d sub, but one that is sealed, will play well with the others.

It was a leap of faith when I decided to go sealed. So many people advise the opposite, and they are 100% right for large or open rooms. To get LFE effects you need raw spl output first. Sealed is more $ for the same spl output (more/bigger subs) so its really a question of what is practical for space and $ I think.

Sealed subs typically tune lower frequencies, can hit lower notes in a box of comparable size.
I'm fairly sure that thought isn't one of the many myths about sealed subs, but i haven't read on them in some time though Audioholics notes on it say something different (i think).
http://www.audioholics.com/loudspeaker-design/sealed-vs-ported-subwoofers

A summary of opinions that SVS has on their webpages:
http://www.svsound.com/t/sealed-vs-ported

Good articles Chess.

Hey brwsaw, have you heard any specifics on when/how much the new ep400 tandems are expected? Hopefully they come in under 1700$. Would be compeition for other dual promotions out there.

I'd love for Axiom to knock this one out of the park, as dual subs are really spectacular.

What I got from those articles is that sealed rolls off more slowly the deeper you go, but ported has more output (SPL) down to its roll off (which is much sharper, but can be just as deep with the appropriate ports and size).

You bring up a good point though. All comparisons are of smaller sealed subs vs. larger ported ones. Where are the comparisons of the large sealed vs same sized large ported?

All in all, a good sub is a good sub. By reducing issues with my room (bass traps and acoustical treatments) plus adding a second sub (both are ported) I've noticed a lot more "punch" to my bass and that is great. I wouldn't say that the bass response in my room is "boomy" at all or as my wife puts it "flabby sounding." I am only assuming that I would get even MORE punch/kick if I added a sealed sub to the mix. Then I would hopefully have the best of both, and hopefully not some strange acoustical weirdness. LOL

Thanks for those 2 articles. Good stuff.

I had an overly long winded post lined up and deleted it. If you lived closer Nick, I'd lend you mine to try. They are boxed up anyways.

The rolloff in sealed is made up by better room gain. There is a thread at HTS where 2 sealed subs dug down to 9hz in a room your size at over 90db. This only works in enclosed spaces of reasonable size. I'll try to dig up a link. Cool stuff.

Here it is. Graphs and iterations galore. A cool thread for sealed info.

http://www.hometheatershack.com/forums/svsound/77026-dual-sb-2000s-flat-10hz.html

I have no reason to suspect Axiom sealed units would perform at anything less than these tests suggest. Two ep500s sealed would probably be similar to the test here. Maybe even 2 ep400s.

Hey, I'm not switching. Too much time and energy in my 2 ported subs that I really like. So stop trying to convince me. LOL

I've always wondered what would happen if I "plugged the ports" on my 2 subs? Might have to play with that someday.

Have we derailed this thread enough to meet normal Axiom forum standards?

Nothing yet, just what's been posted here.

At the moment I'm working with a 12", 2x10" and an 8" sub. 2 ported, 2 non, each paired with its polar opposite (my best ported with the worst non, the best non ported with the worst ported).

Today I had time to scale down the screen size and adjusted the image to suite.

FWIW, I'd be willing to power the new subs with a separate amp. Not sure if there might be some savings there, 1 amp to 2/3/4 subs.

Note that room gain affects ported and sealed subs equally. The slower rolloff inherent in the sealed sub(not taking into account room gain)can make for a more extended bass response after room gain is factored in.