OB and Sealed Subs together

BrandonB

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OB and Sealed Subs together
« on: 12 Mar 2026, 02:33 pm »
Is anyone using OB subs and sealed subs together.  I have read in other threads people will use a sealed sub while watching movies.  If you use them together how do you set it up? 

Danny Richie

Re: OB and Sealed Subs together
« Reply #1 on: 15 Mar 2026, 10:44 pm »
We did several shows where we had open baffle servo subs in the front of the room and a pair of sealed box servo subs in the back corners of the room running out of phase from the front subs and only up to about 25Hz. They really took away the room boom across the back wall and helped balance out the sound.

BrandonB

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Re: OB and Sealed Subs together
« Reply #2 on: 17 Mar 2026, 04:51 pm »
We did several shows where we had open baffle servo subs in the front of the room and a pair of sealed box servo subs in the back corners of the room running out of phase from the front subs and only up to about 25Hz. They really took away the room boom across the back wall and helped balance out the sound.
I have a medium room about 21x15. What size subs would you use in the back and do they need to be exactly in the corner?  I have a set of double doors in one the corner  in a recessed space 4 foot wide 2 feet deep.  I also have a couch about three feet away from the wall.  Is this something that 1 is OK but 2 is better?

Huskerbryce

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Re: OB and Sealed Subs together
« Reply #3 on: 17 Mar 2026, 06:12 pm »
I employ both open baffle double troubles and 3 sealed rythmik 15” subs.  One sealed is on the right wall 3/4 of the way to the back of the room.  The other is a massive dual opposed 15” sealed in the back corner.  The bass response is basically flat with proper sub adjusting.  I would never go back to one sub.

Huskerbryce

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Re: OB and Sealed Subs together
« Reply #4 on: 17 Mar 2026, 07:47 pm »
The setup process is a exactly that.  A process.  First thing I did was to integrate my OBs with the mains.  I treat my mains and my OBs as one full range speaker pair.  The OBs are “always on” so to speak.  I used room eq wizard and my ears with some familiar music.  First step was level matching.  Second step was phase.  Then re-level match after you phase align them.  Once that was complete I moved on to the sealed sub that was the farthest away from the OB subs. 
That step consisted of level matching.  Then I adjusted the phase.  The rear sub is slightly out of phase with the OBs.  This was accomplished by running a baseline low frequency sweep with just the OBs.  Then a baseline sweep with just the sealed sub.  Saved those graphs.  Then ran a sweep with both subs on.  There was a massive dip around 30hz now.  The subs were fighting each other at that frequency.  Adjusted the phase or “distance” of the sealed by 1 ft increments and each time ran a sweep.  I found a distance that made the room most happy.  Then level re-matched both sets of subs to the mains.
Third sub I did the same thing.  Level matched it.  Then played a sweep with all three sets of subs running.  Another big dip appeared around 40 hz.  (The crossover point for that sub).  It was fighting the other subs there.  Adjusted the distance at 1 ft increments and ran a sweep each time.  Finally found the distance that made the graph happy.  Then level matched all the subs to the mains again.  Remember the more subs you have there is an additive property to the level.  Then I played familiar songs and slightly tweeked the distances (by an inch at a time) of the two sealed subs until I liked the sound best to my ears.  Re ran the bass sweep and looked at what I had.  I was very happy with it and saved my settings.  Done.

g3rain1

Re: OB and Sealed Subs together
« Reply #5 on: 21 Mar 2026, 02:21 am »
I've got a massive hole at 43Hz that won't go away no matter the settings are on my subs. I'm wondering if I just need more the balance the room modes.

Theronbo

Re: OB and Sealed Subs together
« Reply #6 on: 11 Apr 2026, 05:20 am »
I use ported subs with Dolby Surround only.

But, considering I also use Apple Music for streaming … it means I use them a lot for general music listening.

System: 7.2.4 surround in a 20x30’ room with 11.5’ ceilings.

I built all the speakers EXCEPT 2 ported subwoofers: JBL 12” & Polk 12” … plate amps on both failed after about a year. Replaced with equivalent plat amps from Parts Express… though I think the PE amps are more real power & have now lasted years.

x-Statics wired through high band pass filters, full output goes to  Double Trouble OB subwoofers… have a couple of mono blocks to feed the X-Statics after filtering 1st Octave (-63Hz).

I do like this setup. The DT subs are amazing musically. & the porters do generous with explosions & earthquake effects.

In Stereo mode it’s just the DTs & X-Statics … the high band pass filters I’ve effectively made the two speakers an integrated 4-way speaker design… Danny might disagree with this opinion.


Anyway the system works great for HT, Apple ‘Spatial’ music … or even Stereo.

Note, if you haven’t listen to Billie Elish or Taylor Swift or The Maria’s or even Domonique Fils-Aimè in Surround Sound you haven’t listen to their music … not really.  They engineered the Surround Mix … it’s so much more interesting than the synthetic after the fact automated mixes…

BrandonB

  • Full Member
  • Posts: 559
Re: OB and Sealed Subs together
« Reply #7 on: 11 Apr 2026, 08:16 pm »
The setup process is a exactly that.  A process.  First thing I did was to integrate my OBs with the mains.  I treat my mains and my OBs as one full range speaker pair.  The OBs are “always on” so to speak.  I used room eq wizard and my ears with some familiar music.  First step was level matching.  Second step was phase.  Then re-level match after you phase align them.  Once that was complete I moved on to the sealed sub that was the farthest away from the OB subs. 
That step consisted of level matching.  Then I adjusted the phase.  The rear sub is slightly out of phase with the OBs.  This was accomplished by running a baseline low frequency sweep with just the OBs.  Then a baseline sweep with just the sealed sub.  Saved those graphs.  Then ran a sweep with both subs on.  There was a massive dip around 30hz now.  The subs were fighting each other at that frequency.  Adjusted the phase or “distance” of the sealed by 1 ft increments and each time ran a sweep.  I found a distance that made the room most happy.  Then level re-matched both sets of subs to the mains.
Third sub I did the same thing.  Level matched it.  Then played a sweep with all three sets of subs running.  Another big dip appeared around 40 hz.  (The crossover point for that sub).  It was fighting the other subs there.  Adjusted the distance at 1 ft increments and ran a sweep each time.  Finally found the distance that made the graph happy.  Then level matched all the subs to the mains again.  Remember the more subs you have there is an additive property to the level.  Then I played familiar songs and slightly tweeked the distances (by an inch at a time) of the two sealed subs until I liked the sound best to my ears.  Re ran the bass sweep and looked at what I had.  I was very happy with it and saved my settings.  Done.

Thank you for that in depth description. 

goggle1824

Re: OB and Sealed Subs together
« Reply #8 on: 12 Apr 2026, 01:12 pm »
I've got a massive hole at 43Hz that won't go away no matter the settings are on my subs. I'm wondering if I just need more the balance the room modes.

That sounds like room nodes to me, hopefully some more knowledgable folks will chime in and offer some options for you to try.

You may be able to help further by sharing a few pictures and/or a description of what treatments you currently have in place or have tried.