# Sub placement, corner vs centre



## tonyvdb (Sep 5, 2007)

Hi everybody, I was doing some reconfiguring of m,y theater room and after removing the audio credenza that I had all my AV gear on or in. It sure made the front of my room much cleaner looking. I decided to try placing my SVS PB13u in the centre under my screen (it was in the right corner) and was pleasantly surprised as to how much more even the bass seemed and it still seemed to have as much physical impact as it did before. 
I have not run REW yet but I seem to think that its smoother.


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## morca (Aug 26, 2011)

I always corner them,but use dsp to level the cornergain/roomgain.
Depending on the room.


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## ALMFamily (Oct 19, 2011)

Tony,

After moving mine all over the room and running sweeps at each location, I found that 2 of my 3 subs are not located in a corner. Odd I know, but I think it really proved to me that the room is the single most deciding factor when it comes to good sound.


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## tonyvdb (Sep 5, 2007)

Ya, it surprised me that it would be this way. The LFE seems to be much less focused and feels more natural.


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## morca (Aug 26, 2011)

The best would be indeed to test al the place,s you can put it.
And than use REW.

I had 1 of them in the middle of a long wall,it was terible.
The one on the longwall ,had to much midbass en cloud be localized.

Now i have them both in 1 corner,sound awesome.
Much more low output in the sweet spot/my chair,and playing whit more detail.

How a sub in a room sounds depends on:

1 the space, the dimensions and shape of the room.

2 what is in the state space (furniture, etc., but also eg bass traps: google: ie acoustic measures)

3 the position in space of the sub relative to the listening position.


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## tonyvdb (Sep 5, 2007)

Its not an easy sub to move around given its over 150lbs! I think I will leave it here for now till I run REW and see what it says compared to my last readings.


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## morca (Aug 26, 2011)

Maybe you can putt it on weel,s  
No kidding i have seen members look for the best location for the sub.
The sub placed on a shelf with wheels.


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## tesseract (Aug 9, 2010)

I've heard impressive bass from placement like you have found, Tony, and REW measurements were used to determine that placement.


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## Todd Anderson (Jul 24, 2009)

Tony - when I installed my new subs I tried multiple locations... Primarily based on the audioholics sub placement recommendations (and also a white paper on sub placement that I can't recall at the moment). At any rate, I found that my dual subs sounded the best (and REW showed this) placed more inward along my front wall (as opposed to corners)... Better than any of the recommended dual sub placements. 

Head scratcher from the perspective that the most unconventional placement proved to be the best. But, every room and response are different, I guess.


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## tonyvdb (Sep 5, 2007)

I think one thing I noticed is that even though your not supposed to "hear" where the sub is located I still found that I could tell it was in the corner. I run my crossover on all speakers at 70Hz except my mains that I run full range but with the Double bass setting on. 
With it in the center of my mains I cant tell where it is.


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## Todd Anderson (Jul 24, 2009)

I know exactly what you are talking about. My old single sub, corner placement, definitely had a lopsided feeling to it.


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## asere (Dec 7, 2011)

If corner placement gives the flattest response is that the best place or not necessarily?


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## hjones4841 (Jan 21, 2009)

As others have said, corner placement will almost always provide the most gain. But, it "excites" more room modes and, therefore, may not provide the flattest freq response. Trial and error is the only way to know where the sub(s) will sound the best. Measuring with REW and a calibrated mic will help find the best spot.


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## asere (Dec 7, 2011)

hjones4841 said:


> As others have said, corner placement will almost always provide the most gain. But, it "excites" more room modes and, therefore, may not provide the flattest freq response. Trial and error is the only way to know where the sub(s) will sound the best. Measuring with REW and a calibrated mic will help find the best spot.


How do you use REW ?


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## tonyvdb (Sep 5, 2007)

asere said:


> How do you use REW ?


Have a look here


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## asere (Dec 7, 2011)

tonyvdb said:


> Have a look here


Thanks for the link but how will I know what the test results mean? I do not know a thing about graphics or how a response should be other than use an spl meter and do a sub crawl, find the flattest response is all I know.:scratch:


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## Dwightlf (Feb 9, 2012)

tonyvdb said:


> I think one thing I noticed is that even though your not supposed to "hear" where the sub is located I still found that I could tell it was in the corner. I run my crossover on all speakers at 70Hz except my mains that I run full range but with the Double bass setting on.
> With it in the center of my mains I cant tell where it is.


I to used to find that the case with a single sub in the corner or on side. I am a real proponent now of dual stereo subs with an active crossover as a result. I like the integration when it is set up right but it is harder to set up and limits your location options. In my room, flat to the wall is NOT the way to go. Angled in is better for reducing room resonant bumps around 50Hz and up, aimed at or close to the listing position seems best as it adds impact. LOTS of testing and listening/moving is the best way to find that “sweet spot.”


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## phreak (Aug 16, 2010)

I like dual subs on the front wall Left-Sub1-Center-Sub2-Right. Audyssey XT32 balances everything nicely. I would recommend corner loading if you don't have enough sub and need the extra gain. I've never tried the "sub crawl" method, but I've heard that it is effective.


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## asere (Dec 7, 2011)

Does it matter how far away or close subs are to each other? I have one on the left corner of the front wall and the other on the left corner of the side wall. Approximately 5ft from each other.


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## hjones4841 (Jan 21, 2009)

asere said:


> Does it matter how far away or close subs are to each other? I have one on the left corner of the front wall and the other on the left corner of the side wall. Approximately 5ft from each other.


If you put them close together, additional output is available via co-location. Works best if both subs are the same model. Co-location "works" as long as the subs are within 1/4 wavelength or so of the lowest frequency they will produce. But, there is a tradeoff as always. Co-location means that you will not benefit from the freq response smoothing of having the subs in different parts of the room.


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## asere (Dec 7, 2011)

hjones4841 said:


> If you put them close together, additional output is available via co-location. Works best if both subs are the same model. Co-location "works" as long as the subs are within 1/4 wavelength or so of the lowest frequency they will produce. But, there is a tradeoff as always. Co-location means that you will not benefit from the freq response smoothing of having the subs in different parts of the room.


When you say smoothing in what way is it different than output?


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## ALMFamily (Oct 19, 2011)

asere said:


> When you say smoothing in what way is it different than output?


Pretty sure he is referring to your frequency response. While you can normally get a pretty good FR at the primary LP with one sub, other seats are not so lucky. Adding the additional sub in a different location helps to "smooth" out your frequency response across multiple seats.

Output is strictly that - an increase in SPL. IIRC, adding the additional sub does not result in a huge SPL boost - something like 3 db pops into mind.....


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## asere (Dec 7, 2011)

ALMFamily said:


> Pretty sure he is referring to your frequency response. While you can normally get a pretty good FR at the primary LP with one sub, other seats are not so lucky. Adding the additional sub in a different location helps to "smooth" out your frequency response across multiple seats.
> 
> Output is strictly that - an increase in SPL. IIRC, adding the additional sub does not result in a huge SPL boost - something like 3 db pops into mind.....


Gotcha, right now both of my subs are close to one another. One is front left corner and the other on the corner of left wall. Tomorrow I will move the one on the corner of left wall to the front right corner so that way one will bee on the left and other on the right. Right now how they are I get nice output in mlp because they are close but in moving seats I don't get the same output. I will just try that to smooth and get even bass. Thanks!


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## yoda13 (Feb 14, 2012)

this yielded me better results









than this









sonically anyway. Not so much output, but just sounded better after the sub crawl. The more in the center I was crawling (by the center speaker), the worst it was not to mention that there must be one massive null there 'cause I could barely discern anything there.


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## asere (Dec 7, 2011)

yoda13 said:


> this yielded me better results
> 
> than this
> 
> sonically anyway. Not so much output, but just sounded better after the sub crawl. The more in the center I was crawling (by the center speaker), the worst it was not to mention that there must be one massive null there 'cause I could barely discern anything there.


Nice set up. I will try it on the corners like your first picture. Thanks for providing pics!


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## koyaan (Mar 2, 2010)

I've tried subs in opposing corners only to find the bass completely missing in the center of the room. They will cancel one another out and create a dead zone.


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## asere (Dec 7, 2011)

Can you have one sub in a corner with flattest response and have the second in a different corner with not as flat response?


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## yoda13 (Feb 14, 2012)

koyaan said:


> I've tried subs in opposing corners only to find the bass completely missing in the center of the room. They will cancel one another out and create a dead zone.


if they are facing each other, perhaps yes, but you can always use the phase switch behind on of the sub.


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## asere (Dec 7, 2011)

Can you have one sub in a corner with flattest response and have the second in a different corner with not as flat response?


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## asere (Dec 7, 2011)

Sorry about duplicate question. I can't delete one.


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## asere (Dec 7, 2011)

I just place the subs on the left and right corner of the front wall. I did lose output but got even bass distribution.


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## morca (Aug 26, 2011)

yoda13 said:


> this yielded me better results
> 
> 
> 
> ...


Very nice setup.
The first picture show,s maximum use of cornergain.
Do you use any form of DSP for the sub,s.


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## asere (Dec 7, 2011)

I hear two subs don't sound louder. I'm my room they do. Is that how it should be?


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## ALMFamily (Oct 19, 2011)

asere said:


> I hear two subs don't sound louder. I'm my room they do. Is that how it should be?


They actually do - IIRC, you will see something in the neighborhood of a 3 db increase.


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## asere (Dec 7, 2011)

Can one sound slightly louder than the other? I had to level match the gain and Audyssey multeq sees them as one. Subs are mismatched.


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## hjones4841 (Jan 21, 2009)

koyaan said:


> I've tried subs in opposing corners only to find the bass completely missing in the center of the room. They will cancel one another out and create a dead zone.


Have you tried changing the subs' phase? Usually there is a switch or knob on the amplifier.


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## hjones4841 (Jan 21, 2009)

asere said:


> Can one sound slightly louder than the other? I had to level match the gain and Audyssey multeq sees them as one. Subs are mismatched.


Could be because of room acoustics. Also could be that one is better at some freqs than the other one. Audyssey takes an average of the two, which does not always mean that both will sound the same. An AVR with XT32 and two sub outputs might do a better job, but one of those would cost about the same as upgrading one of the subs.


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## asere (Dec 7, 2011)

hjones4841 said:


> Have you tried changing the subs' phase? Usually there is a switch or knob on the amplifier.


How will I know if phase is off and on which sub?


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## asere (Dec 7, 2011)

hjones4841 said:


> Could be because of room acoustics. Also could be that one is better at some freqs than the other one. Audyssey takes an average of the two, which does not always mean that both will sound the same. An AVR with XT32 and two sub outputs might do a better job, but one of those would cost about the same as upgrading one of the subs.


My kreisel 12012 is more capable then my hsu vtf3 mk4 yet kreisel sounds softer when running together.


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## Dwightlf (Feb 9, 2012)

asere said:


> Can one sound slightly louder than the other? I had to level match the gain and Audyssey multeq sees them as one. Subs are mismatched.


Yes, if the if the distance in form the back wall, side wall and angles are not the same or if the room is different on one side from the other or if the subs are not set the same in setting or ports. I agree with the Audyssey statement too taking an average. Can you test the subs as separate in and out for each with the Yamaha? Can you make SPL measurements? If so, do a close (1m or so) spl from each at various frequencies or with a SLOW sweep and see if they can be matched by volume. Changing the phase could help but see what effect it has in the listening position for depth and impact.


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## Dwightlf (Feb 9, 2012)

tonyvdb said:


> Ya, it surprised me that it would be this way. The LFE seems to be much less focused and feels more natural.


How did your REW measurements come out BTW?


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## tonyvdb (Sep 5, 2007)

I have not done them yet, I ended up heading out of town this past weekend so I will try to do it Thursday evening if I have time.


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## asere (Dec 7, 2011)

Dwightlf said:


> Yes, if the if the distance in form the back wall, side wall and angles are not the same or if the room is different on one side from the other or if the subs are not set the same in setting or ports. I agree with the Audyssey statement too taking an average. Can you test the subs as separate in and out for each with the Yamaha? Can you make SPL measurements? If so, do a close (1m or so) spl from each at various frequencies or with a SLOW sweep and see if they can be matched by volume. Changing the phase could help but see what effect it has in the listening position for depth and impact.


Yes the corner were the hsu is it's different than the kriesel corner. I might try placing the kriesel were the hsu is since kreisel is the superior one.


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## asere (Dec 7, 2011)

How come my sub makes a humming noise when connected to a plain rca cable. My other sub is connected to an interconnect cable


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## tonyvdb (Sep 5, 2007)

Is it plugged into the same power outlet?


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## asere (Dec 7, 2011)

tonyvdb said:


> Is it plugged into the same power outlet?


No one to the line conditioner and the one that hums to regular outlet. It does not reach the conditioner.


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## tonyvdb (Sep 5, 2007)

Thats more than likely the issue, you probably have a ground loop hum.


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## asere (Dec 7, 2011)

tonyvdb said:


> Thats more than likely the issue, you probably have a ground loop hum.


Do I need to disconnect it from the wall then. Will it harm the sub?


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## tonyvdb (Sep 5, 2007)

You should if possible just run an extension cord over to the same conditioner the other sub is plugged into.


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## asere (Dec 7, 2011)

tonyvdb said:


> You should if possible just run an extension cord over to the same conditioner the other sub is plugged into.


Any extension chord?


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## B- one (Jan 13, 2013)

Maybe a new power cord if the extension cord works. You seem to have nice subs I would hate to have issue from a extension cord that may affect warranty possibly not sure about it but just a thought.


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## asere (Dec 7, 2011)

B- one said:


> Maybe a new power cord if the extension cord works. You seem to have nice subs I would hate to have issue from a extension cord that may affect warranty possibly not sure about it but just a thought.


Can I actually get rid of the power cord that came with the sub and buy one long enough? If so what power cord?


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## asere (Dec 7, 2011)

Well my Hsu and Kreisel subs sound amazing together. It took me awhile to find the right placement area and figure which one goes were since they are mismatched. Most people say mismatched subs are not a good idea and I agree to a point but If you get it right its amazing how much of a smooth sound you get with two. In my case the Hsu being the inferior one should not bottom out since I normally listen around 40-50 db. Now all I need is a longer IEC power cord so I can connect the Kriesel to the line conditioner to get rid of the ground loop hum.


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## B- one (Jan 13, 2013)

You should try calling manufacturer they should be able to help if they can't an electrician could do it. If your good at electric you can get a suitable cable from electric supply company take the cable there and they could hopefully set you up with the other parts. You maybe able to reuse the ends of your cord even but I would ask them to be safe.


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## B- one (Jan 13, 2013)

Ps good job getting the subs working together. I only have one not sure someone would let me have 2.


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## tonyvdb (Sep 5, 2007)

Ok, finally got to do a reading with REW this is what I got.


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## Dwightlf (Feb 9, 2012)

tonyvdb said:


> Ok, finally got to do a reading with REW this is what I got.
> 
> 
> Looks nice! do you like the ballance?


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## tonyvdb (Sep 5, 2007)

It seems as I said very smooth, its not so forward in the place I have it now. I am a bit confused by the reading as my crossover is set at 80Hz but by looking at the graph there still seems to be info up to 90Hz before it drops. Im wondering if it has to do with the fact I have "double bass" turned on in my receiver although I thought that simply just added the lows to my mains as I run them full range.


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## tesseract (Aug 9, 2010)

Crossover settings are not always precise, the AVR may be set at 80 Hz but filtering at 90 Hz.

Nice room response you are getting, Tony.


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## Dwightlf (Feb 9, 2012)

tonyvdb said:


> It seems as I said very smooth, its not so forward in the place I have it now. I am a bit confused by the reading as my crossover is set at 80Hz but by looking at the graph there still seems to be info up to 90Hz before it drops. Im wondering if it has to do with the fact I have "double bass" turned on in my receiver although I thought that simply just added the lows to my mains as I run them full range.



It looks ok to me and if it sounds good, that’s the goal. You can have some error in actual crossover settings (my DBX is off by about 5Hz, but more than likely there was a bump in that area before adding the crossover. If the measurement of the Frequency response with he subs and mains measured is showing a bum at 90Hz or if you hear a bloom in that range, try lowering the crossover point to see if it helps. I would leave it if you’re not hearing a rise at 90Hz though.


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## tonyvdb (Sep 5, 2007)

Yup, after some fiddling this is my final reading with sub and mains together. Yes I do run my sub a little hotter than my mains as I like it that way.


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## asere (Dec 7, 2011)

tonyvdb said:


> Yup, after some fiddling this is my final reading with sub and mains together. Yes I do run my sub a little hotter than my mains as I like it that way.


What does the green and blue line mean and same for the vertical and horizontal numbers? Excuse my ignorance I'm completely lost since I don't know how to read it. Learning here and thank you!


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## tonyvdb (Sep 5, 2007)

The blue line indicates the crossover slope of the sub and the green line is the frequency response of the sub and main speakers in my room. The 15Hz line is what I have the PB13u set at to roll off at.


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## Dwightlf (Feb 9, 2012)

tonyvdb said:


> Yup, after some fiddling this is my final reading with sub and mains together. Yes I do run my sub a little hotter than my mains as I like it that way.
> 
> :bigsmile:
> Looking good! I agree, I always end up with the subs up about 6 to 8 db ;-) It measures the higher you go dropping slowly from a listening position with the mike not pointing directly at the main anyway. Have fun listening!


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## Dwightlf (Feb 9, 2012)

It’s a wonderful sickness I say, audio is. After following your re-setup I had to play. Moved, measured and played stuff all day. Speakers are in a more centered position much to the chagrin of my wife. Now the system REALLY dominates the room.

Ah but the sound, the Bass! Do we ever get satisfied???


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## tonyvdb (Sep 5, 2007)

LOL, never. Thats the joy of this hobby and the thing is you dont have to spend a dime and make a big change in sound.


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## asere (Dec 7, 2011)

Audyssey set my subs at +5 and sounds good to me however my wife thinks it plays too loud with tv shows. I went into the avr and changed the sub trim to -8. Is a trim this low acceptable without causing issues with subs? Can I even do -12 just for tv viewing? For movies I still leave it at + 5 LOL!


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## tonyvdb (Sep 5, 2007)

Adjust it all you want, it wont hurt anything.


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## asere (Dec 7, 2011)

tonyvdb said:


> Adjust it all you want, it wont hurt anything.


thank you!


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## asere (Dec 7, 2011)

I have both subs running together and they sound nice however, I am curious to know how much different are they based on specs and if it is a good idea to use both or just one? I can tell you that the subs have given me smooth response across all listening areas. If it's going to be just one for sure I would just use the Kreisel. Thanks in advance!

KREISEL DXD-12012 
Driver Configuration DUAL PUSH-PULL 12” HIGH VELOCITY DEEP BASS DRIVERS 
Typical in Room Frequency Response 10 Hz - 200 Hz 
Variable Phase Adjustment 0 to 180 degrees 
Variable Low Pass Filter Range: 40Hz - 160Hz at 12db per Octave 
Variable Bass Level with Switched Fixed Calibrated REFERENCE LEVEL Setting 
Variable Low Pass Filter Bypass Switch 
Auto On/Off switch Only operates when using the RCA inputs 
Unbalanced RCA LFE/Line Inputs 2 
Impedance for Unbalanced RCA Inputs 8k Ohms 

HSU VTF3 MK4
Amplifier Power (RMS) 1400 W Short Term, 350 W Continuous 
Hybrid Tuning 16 Hz Ported, 22 Hz Ported or Sealed 
Woofer Side Firing 12 Inch 
Q Control Range 0.3 - 0.7 
Crossover 30 - 90 Hz, Bypassable 
Crossover Slope 24 dB/Oct 
Phase 0°/180° 
Inputs Line Level (2), Speaker Level (2) 
Power Outlet Requirement 430 W, 120/240V


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## B- one (Jan 13, 2013)

Why not try it to see which way you like it best. Seems like the easiest way to know for sure.


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## asere (Dec 7, 2011)

B- one said:


> Why not try it to see which way you like it best. Seems like the easiest way to know for sure.


I have tried one at a time and its all good however, running both it sounds better because there is a smooth response all across. I wanted someone to look at the specs just to make sure I am not doing more harm than good to the Hsu running it with the Kreisel. Together they can sound nice but I am concerned that the Hsu can get damaged and I won't know it. Is there too much of a difference in specs?


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## Dwightlf (Feb 9, 2012)

Is your HSU an Mkllll with the option to set it up vented? I think you will not hurt anything by running both unless you drive the woofer to excursion limits and it starts making a loud clicking sound. That is easier to do in a vented system. The BASH amplifier should have overload and thermal protection built in so it would not get harmed. Just be careful to monitor it now and again when you try new material with deep bass at a high level.
Of course there is always a possibility of something happening so I can't be sure but I would run them both and just be careful with loud and deep bass.


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## asere (Dec 7, 2011)

Dwightlf said:


> Is your HSU an Mkllll with the option to set it up vented? I think you will not hurt anything by running both unless you drive the woofer to excursion limits and it starts making a loud clicking sound. That is easier to do in a vented system. The BASH amplifier should have overload and thermal protection built in so it would not get harmed. Just be careful to monitor it now and again when you try new material with deep bass at a high level.
> Of course there is always a possibility of something happening so I can't be sure but I would run them both and just be careful with loud and deep bass.


The KK is sealed only and Hsu is hybrid so it can be sealed or vented.


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## asere (Dec 7, 2011)

Is it normal for the driver to make a rattling noise when it moves lots of air with high spl?


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## tonyvdb (Sep 5, 2007)

If its rattling you are pushing it past its limitations.


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## Todd Anderson (Jul 24, 2009)

I agree... are you sure it's the driver rattling? Subs can definitely cause a lot of different vibrations... could even be the sub cab if it is damaged.


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## asere (Dec 7, 2011)

tonyvdb said:


> If its rattling you are pushing it past its limitations.


I'm not sure if its rattling. I hear it if I get next to the cone. The driver moves super fast with some sort of noise.


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## Todd Anderson (Jul 24, 2009)

Perhaps it's port noise? Is it sealed or ported?


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## asere (Dec 7, 2011)

Todd Anderson said:


> Perhaps it's port noise? Is it sealed or ported?


One is sealed and the other ported.


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## tesseract (Aug 9, 2010)

Trouble shooting tip, eliminate room resonances as a variable. Can you take it outside and listen to it? Or maybe hook it to a garage system, placed well away from any boundaries?


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## asere (Dec 7, 2011)

What happens if you place a sub in an area that does not have a descent flat response?


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## tesseract (Aug 9, 2010)

One never knows until trying it, measurements would help greatly.


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## Tom V. (Jul 12, 2012)

A bit limited in scope but interesting data none-the-less

http://www.nousaine.com/pdfs/Multiple Subwoofers.pdf

Tom V.


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## asere (Dec 7, 2011)

Tom V. said:


> A bit limited in scope but interesting data none-the-less
> 
> http://www.nousaine.com/pdfs/Multiple Subwoofers.pdf
> 
> Tom V.


Interesting information. Thanks for sharing!
Yesterday I used an spl meter and did the crawl noting the different frequencies from 20hz to 80hz and found that along the front wall and corners I have the highest spl's. I moved the sub out of the corner and placed it in the middle of the front wall. The spl is high there but the sub seems to play tighter with movies. Example with Jack Reacher the car scene with the car engine running corner placed the sub had lots of energy and the engine was kinda overwhelming. Now away from the corner that same scene sounds more natural. As far as commercials and tv goes well I think it has to do with how it is recorded because nothing makes that better. I just turn Audyssey completely off for tv and bass lessens.


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## jimmy bobarino (Mar 13, 2012)

Tom V. said:


> A bit limited in scope but interesting data none-the-less
> 
> http://www.nousaine.com/pdfs/Multiple Subwoofers.pdf
> 
> Tom V.


Very interesting indeed, it seems most of his other articles tend to support one subwoofer in the corner as well.


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## tonyvdb (Sep 5, 2007)

Its very dependent on room dimensions and furniture placement. I his situation it worked but with others it may not be ideal.


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## asere (Dec 7, 2011)

tonyvdb said:


> Its very dependent on room dimensions and furniture placement. I his situation it worked but with others it may not be ideal.


In my situation it worked too. By not getting energized with my corners the bass is tight but the pressure is smoother.


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## kingnoob (Mar 12, 2013)

I locate both my subs 1-2 foot away from corner so rather close. I need too repair my KLH sub-woofer so Its been off for a few months. :hsd: Sinks the house with massive bass front firing towards center of room located foot from the corner.


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## tba (Jun 10, 2013)

Dear all,
I have carefully read all the replies, because I have been myself in all situations. I started with one sub and regardless of positioning (done by crawl, auto eq, Audissey or any other) I had always unhappy listeners in different locations (in the main sweet spot was ok, but few inches away not). Then I bought another identical sub and tried everything I could, same result. The best position, in my oppinion, was in a corner (front or back) and both subs stacked one to the other. But the same variable response at different seats. I have ended the story by placing four identical subs in each corner, all playing the identical mono signal, all with the same settings, Xover at 62 Hz low pass and 30 Hz high pass, 48 db/octave. Now, nobody can locate the source of the bass and the sound is uniform everywhere regardless the seat.
Regards,
tba


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## charlieblue (Aug 17, 2013)

Sorry for the late post, there are so many threads in HTS and I am slowly going through them... : )

Running this Ripple Tank Applet can help visualize how a sub-woofer activates room modes. 

Run the applet and select "Room Resonance" from the first pull-down menu - it's some 2/3rds down the way. This shows a representation of a room and a point source placed in 4 different positions inside it. To simulate a sub, slide the "Source Frequency" bar to the - not extreme - left.

To make the presentation easier to watch, select "Color Scheme 4" from the 4th pull-down menu. Then slide the "Simulation Speed" to the left to make things run slower and the "Resolution" bar to the left just so as to re-size the "rooms" to your screen. 

What sub placement looks better, the corner, mid-wall or mid room position? And why?


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