Newbie problem regarding placement of multiple subwoofers in oddly shaped room

[Madman4ever]

Hello everyone ,this is my first post on this forum ,and i am in need of some help.
The basic issue is with the placement of 4 subs in an attic room with an oddly shaped ceiling and mostl of the walls covered in drywall
The 4 subs are :
1 JBL ES250PW
2. SVS PB-12 NSD
3. XTZ 99 W12.16 S Left
4 .XTZ 99 W12.16 S Right
Im also using a Yamaha RX-A2010 receiver ,1 and 2 are connected to subwoofer 1 and 2 on the receiver and the XTZ subs(3+4) are daisy chained from the low pass of the SVS sub.
Also using an Anthem 225 to power my main front Paradigm studio 100 speakers.

I have attached a picture that explains everything about the room and placement.
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The bass at this moment in the room is quite adequate when watching movies that have a very good LFE track , but with any kind of music the bass is quite lacking in the central sitting positions at least.
Overall there is a general absence of bass in the central two sitting positions and very much bass near the left and right couches and in the very back of the room behind the bar.

I would love some input.

 

[j_garcia]

How did you choose the locations of the subs? Have you tried this?

Crawling for Bass - Subwoofer Placement Tips | Audioholics

Why do you have so many different subs? I'd eliminate the JBL, like literally, with fire, eliminate it. Do you have a receiver with Audessey that has the ability to calibrate multiple subs? If not, how have you calibrated these subs?

A peaked room like that is going to create issues for bass, and probably sound period. IMO, you're going to need to look into some room treatments in addition to careful calibration.

 

[Madman4ever]

The JBL i can return , I've only recently got it , only reason i have it is because its wireless and i cant really run cables where it's placed at the moment.
The Xtz ones i got because i really liked how they sounded with music and as a lot of people have noticed that PB-12 NSD sub while absolutely great with movies explosions etc is quite slow for music

I'm using an Yamaha RX-A2010 receiver for my system which has YPAO , i can calibrate phase, distance ,+/- DB from the receiver on the SVS and JBL subs which are set as subwoofer 1 and subwoofer 2 in dual mono mode (other options are Left/right and front/back for the subs) , the XTZ subs are connected to the PB12-NSD in series.
All sub-woofers are at 0 degrees phase.

Speakers crossovers are set to : small front 60HZ , small center 100 hz , small surrounds 80 hz

 

[j_garcia]

The calibration is going to be wrong for the XTZ subs connected this way though. Disconnect the JBL, use sub 1 for the SVS and sub 2 for XTZs and see how it does. How about placement? How did you determine where to place them in this room? That's going to be a big factor with multiple subs and a difficult room.

 

[Madman4ever]

Regarding placement, the SVS was in the right corner near the right front speaker, but i felt it was very boomy and there was a lot of reverberation in the walls hence i moved it a bit further back near the couch on the right,sound wise i didn't notice any difference only less rumble in the drywall
As for the XTZ ones that"s about the only place i figured can place them since they seem to be directional or so i thought.

Only other places I have in the room from placing any of the subs is behind the bar or in the lower right corner where the small speaker is and where i originaly placed the Pb-12NSD in the upper right corner near the right front speaker
Upper left corner is a no go since the door opens right into the left speaker, lower left corner near the door above the bar is a no go aswell since the door opens there.

Would connecting the XTZ subs to the Anthem 225 (im using it is as power the front pair) pre outs as left/right be better? Also does the position of the driver relating to seating location have any impact ? Do i need to rotate any of them (for example the NSD rotated to be facing towards the central seats)?

 

[j_garcia]

If they are front firing, when aimed at you and sitting close, yes it will have an impact on the sound. Bass below about 100Hz is not directional, however sitting that close, you will hear a difference when changing orientation of the driver IMO; mainly higher up as opposed to the bottom octave.

Left/right preouts will give you full range signal when set to large, which creates a different issue - you now have to adjust the x-over and blend to your mains yourself. You are better off using the sub pre-outs (mono, bass managed by the AVR) if you ask me.

 

[Madman4ever]

Got it ,move the XTZ's to sub 2 (keep them chained) on the receiver and keep it set to dual mono redo YPAO , but is placement ok as they are now (firing towards the side of the left and right center seats)?
Keep NSD where it is and maybe rotate it facing the center seats?
One last thing about the JBL, do I absolutely need to return it , is it that bad of a subwoofer?

 

[j_garcia]

I don't think it is a benefit to you in this particular system and room IMO, but there's no real reason to return it if you're happy with it. I only recommended that because in a mult-sub setup, it is desirable to have identical ones if possible and at least comparably capable ones. In this case, the JBL probably isn't bad, but is nowhere near the SVS and possibly the others as well. I'm not familiar with the XTZ specs, but at least they are the same, though I find it odd that anyone would call a sub "left" or "right simply because bass is non directional. See how it does with the current placements and then adjust as necessary. Even with YPAO it can take a few different tries with things in different places/orientations to get it to sound the way you want.