# Placement of sub woofers and TubeTraps



## glabelle (Nov 13, 2014)

I can't find anything specifically about this, so before I go measuring SPLs and moving speakers around, I thought I'd query the group about this.

I have a 16X23X10' room. Before building it, I consulted with ASC and got 2 tubetraps and a bunch of sound panels. The 16" Dia. 4' long tubetraps were placed in the front corners, on the floor.

My main speakers (2X B&W 802SIII and an 801SIII center - behind a Stewart acoustically transparent screen)) are 4' from the rear wall. I have 2 Velodyne ULD-15 subwoofers at the 1/3 points along the rear wall (just added). Sounds good, but I want to make sure it is optimum.

I don't know the effects of putting tubtraps where maybe the subs should go. Or maybe I ought to put the subs on top of, or below the traps, or? I guess I just don't understand the interaction between tubtraps and subwoofers. Any help in this matter appreciated.

George


----------



## mollie (Feb 27, 2014)

glabelle said:


> I can't find anything specifically about this, so before I go measuring SPLs and moving speakers around, I thought I'd query the group about this.
> 
> I have a 16X23X10' room. Before building it, I consulted with ASC and got 2 tubetraps and a bunch of sound panels. The 16" Dia. 4' long tubetraps were placed in the front corners, on the floor.
> 
> ...


First measure on which frequency(ies) standing waves are showed. These are loud so look for the maximum Sound Pressure Level(s)at listening position.
Usually the traps will be positioned at the opposit wall (or corners) as where the speakers are placed. (best pos.speakers on short side of the room)
Traps should be adjusted (if possible) to the center frequency of the standing wave peak to abzorb this peak optimal.
The soundpanels could be used to abzorb or to overcome reflection problems (on side or backside of speakers) in mid and higher frequency areas.
Succes


----------



## glabelle (Nov 13, 2014)

So you are saying that Tube Traps should be placed in the back of the room?

Thanks, George


----------



## mollie (Feb 27, 2014)

glabelle said:


> So you are saying that Tube Traps should be placed in the back of the room?
> 
> Thanks, George


That is not always the case, but usually it is very often the right position.
You could try by moving them around the room and listen or measure at the listening position.


----------



## Tonto (Jun 30, 2007)

Tube traps generaly are designed to absorb a particular frequency (if I'm understanding what you have). I would find out what yours are designed to capture, then measure your room with REW to see if those frequencies are a problem. If they are, put the tube traps in various places & see how they are affecting your room responce @ the PLP. If they are covering a portion of the rooms responce that is not problem, don't use them. Always helpful to measure the room first.


----------



## WLDock (Dec 19, 2009)

Great layout ideas here: http://www.tubetrap.com/tubetrap-layouts.htm


----------



## glabelle (Nov 13, 2014)

Well, I have 2 TubeTraps. They are not exactly cheap, and I don't plan on buying more of them, I just want to figure out the best placement for the 2 I have. The ASC site says to start with 4!

None of their information addresses my original problem - how do you coordinate the placement traps with the placement of subwoofers.

Right now, I have the subs in the front corners and the TTs on top of them. Seems "OK". I cannot physically put them in the rear at this time.

George


----------



## Tonto (Jun 30, 2007)

Are you able to measure with REW?


----------



## WLDock (Dec 19, 2009)

glabelle said:


> Well, I have 2 TubeTraps. They are not exactly cheap, and I don't plan on buying more of them, I just want to figure out the best placement for the 2 I have. The ASC site says to start with 4!
> None of their information addresses my original problem - how do you coordinate the placement traps with the placement of subwoofers.
> Right now, I have the subs in the front corners and the TTs on top of them. Seems "OK". I cannot physically put them in the rear at this time.
> George


George, we don't know each other so don't take this the wrong way...... My name is Walter or Walt by the way.

How do you find out about tube traps in the first place? Why did you buy them? Why did you by two instead on one, four, or eight? Do you know what room modes are? Did you at least look around the Tube Trap site and read ALL of the useful info?

Did you see the Users Guide? http://www.tubetrap.com/tubetrap-user-guide.htm

Basic Setup









Room Modes









Advanced Setup









I led you to the water.....

Their site addresses all your questions. The only way to get more in depth is to take REW measurements and your EARS to see where your problems are. Then try to fix them as best as you can with the given materials. Again, YOUR EARS are KEY! Find the sound you are after.


----------



## glabelle (Nov 13, 2014)

Yes, I have REW.
Yes, I know what room modes are.
My original question was a query for advice, before I started making a bunch of measurements and moving heavy stuff all around.

The diagrams you posted, nor any information I could dig up at ASC even mentions mixing subwoofers with TubeTraps, again my original question.

Thanks, George


----------



## rambocommando (Aug 28, 2014)

Could you post pics of your room, or a diagram so that we can see where you could possibly put the tubetraps? As others have said, and posted with pictures, the optimal layout is the tubetraps in a corner and the subs inset from them toward the center. But it sounds like you have some physical obstacles to work around, so pics or drawings would help.


----------



## mollie (Feb 27, 2014)

glabelle said:


> Yes, I have REW.
> Yes, I know what room modes are.
> My original question was a query for advice, before I started making a bunch of measurements and moving heavy stuff all around.
> 
> ...


First measure whether you realy need them at all !!!
Show us a measurement from the listening position!! 
From there you can go on, from whatever is needed.


----------



## Phillips (Aug 12, 2011)

Maybe post on the link below as well.

http://www.hometheatershack.com/forums/home-audio-acoustics/


----------



## WLDock (Dec 19, 2009)

glabelle said:


> Yes, I have REW.
> Yes, I know what room modes are.
> My original question was a query for advice, before I started making a bunch of measurements and moving heavy stuff all around.
> 
> ...


From all that you posted what stands out is that you placed the traps in the corner, you placed the subs 1/3 of the distance between opposing walls, you have a nice money spend on speakers, subs, bass traps, and room treatments, and you have room measuring equipment.

I see you have done your homework and if you continue to read everything there is out there on sub placement and room modes and get as many recommendations on the net there is one thing that will remain the same. You will find that most would agree that in most rooms there is no one ideal placement for sub-woofer/s. Also, generally speaking, placing at least one sub close to the mains will help with integration and phase.

From there the only way to get your money's worth is to do the work or pay someone to do it. Some say your ears are good enough other say science and measurement tools are needed also. Either way, there is a wealth of info on the ASC site that maybe you missed? With two traps I don't see what more you can do but leave them in the corners. As far as subs...that is a different beast!

*Optimizing ASC Tube Traps* - http://www.tubetrap.com/bass_traps_articles/iar89.htm 

*Your Room: The Final Link* - http://www.tubetrap.com/bass_traps_articles/iar85.htm

Additional articles on Subwoofer placement and setup:

Easy to read understand:
*Dual Subwoofer Placement for Your Home* - http://www.aperionaudio.com/blog/dual-subwoofer-placement-for-your-home
Great quote from the article:


> Experimentation is the answer: Since there aren’t any guaranteed best spots when it comes to positioning multiple subwoofers, moving them around and listening for the changes is really the only way to get them locked-in with your lair. But if you have a rectangular room, you can use some general placement guidelines as starting points. Of course, your listening positions will also affect where in the room the subs sound their best. But once you’ve got that dialed in, check out some of the most popular dual subwoofer placement options below: - See more at: http://www.aperionaudio.com/blog/dual-subwoofer-placement-for-your-home#sthash.I6vnRpTW.dpuf


Basic to more in-depth subwoofer setup articles - *Source - * http://www.audioholics.com/subwoofer-setup

*Basic Subwoofer Setup Guide NOT for Dummies* - http://www.audioholics.com/subwoofer-setup/basic-subwoofer-setup

*Crawling for Bass - Subwoofer Placement Tips* - http://www.audioholics.com/home-theater-connection/crawling-for-bass-subwoofer-placement

*Subwoofer Placement - The Place for Bass Part 1* - http://www.audioholics.com/subwoofer-setup/subwoofer-placement-the-place-for-bass-part-1

*Home Theater Multiple Subwoofer Set-Up & Calibration Guide* - http://www.audioholics.com/subwoofer-setup/multiple-subwoofer-setup-calibration-1

*Dr. Earl Geddes* - https://mehlau.net/audio/multisub_geddes/

*Dr. Floyd Toole * - http://www.harman.com/EN-US/OurCompany/Innovation/Documents/White Papers/LoudspeakersandRoomsPt3.pdf


----------

