Anyone have Bookshelf speakers mounted over top of their subs??


Like the title says, I was wondering if many have done this to get a true stereo sound with dual subs, and bookshelf speakers?  My current set up is SVS ultra bookshelves, and 1 SVS sb2000 for now, adding another sub soon. I would like to build speaker stands to where the subs slide under the bookshelf speakers, and I haven't seen it done anywhere, just wondering if it is an idea worth pursuit?
musicjones
Hi Music,

It's been done before, to good effect. this is how Linkwitz makes some of his open baffle systems.

In my HT I cheat, and put the center channel on top of the sub using an IsoAcoustics platform.

Best,

E
It seems logical to me, but I am a bit of an audiophile novice and this is my first real setup. I'm glad someone has gotten good results,  I cant see much of a difference between this and if I had tower/floor speakers, other than the subs will get much lower end response than any tower/floor speakers I could afford. 
Hey Music,

True, but you are missing one important feature. Subs can be placed in acoustically ideal situations, which may NOT be under the monitors.

Sub placement, bass traps and EQ are all critically important in getting good sound out of them. Subs have to integrate to the main speakers as well as to the room.

Do this right and it’s breathtaking.

I would rather have 1 sub well integrated than 2 poorly set up.

Best,


E
I do not disagree,  I have a room treatment ordered, and I am going to build some bass traps myself, or GIK is a local business to me, so I can pick some up there. Right now the one sub I have is sitting midwall and my room is not ideal, so there are some nulls and some boominess. Hopefully the treatments and traps will control the boominess.im not sure how they affect the nulls though.
Unless you're using room correction, this almost certainly a bad idea.  I'd always place the subs for smoothest bass and the mains for best imaging.  If you just make sure that you're crossing low enough from sub to main to eliminate subwoofer directionality, you won't be trading away anything (except appearances) with asymmetrical placement.
I have the sub set at 80hz so directionality isn't too much of my concern, it's more of filling in the nulls, and having better overall sound. I may try facing the 2nd sub directly at the 1st sub on the opposite wall. My room is 11x19 (sub on the 19 foot wall) but there is a stairwell, and a 5 foot entryway to the kitchen,  so sound waves are escaping like a death row inmate. Plus i have wooden sub floors. Not a great scenario, but it's what I'm working with. 

Have you tried the inverted process ?

If you lack measurement tools, which IMHO are essential,  you can put the sub where you sit, and you walk around the room until you hear the best bass. Then swap you and the sub. :)
I did this years ago using Totem Mani 2's with 2 NHT sub two subwoofers. Worked very well. You might not have the ultimate degree of moving the speakers around for the best performance for both the sub and the main speakers, it worked for me
GIK is a great manufacturer, you are lucky to have them nearby.

Bass traps remove the inevitability of nulls. :)

You'll need EQ, but traps + EQ can really do wonders.

I recommend you use a descending target curve, about 1-1.3dB/octave.

Best,

E
There are several professional acoustic articles about this, but yes, you get rid of nulls by using bass traps first, and then EQ becomes possible. The other way around, not so much.

Thank you all for your Input, it looks like my next step is going to definitely be build some bass traps. I have the material to build some 3" thick ones and I am only able to build them about 3' tall due to other things in my living Room that cannot be moved .  I plan on ordering some fabric from Gulliford of Maine to wrap my bass traps in , I think it is probably wise to let my girlfriend to use the color . She has agreed to let me hang acoustic panels on the walls, as long as they are art panels, like the ones offered by Audimute( one of those already ordered) 
Erik, I am not up to speed on my octaves and curves yet , and I am pretty much a novice at home audio. I am very anxious to learn all of the required terminology and technical ability to make what I have sound as good as it can. 

@musicjones - take a really good look at the Owens 703 FRK.  I have used this extensively as well as the Roxul Rockboard 80.  You may end up having better bass absorption with the FRK due to the foil membrane (and it will not absorb the upper mids/highs as much).  You could probably layer a 2" 703 FRK with a 1"/2" standard 703 to get a 3-4" panel.

If you really want an effective bass trap, look at the GIK Monster Bass Trap with the FlexRange Limitor.  This costs money, but the membrane panel does an excellent job of capturing 60-80 hz and also does not absorb the high frequencies (which can suck the life out of a room).

In terms of eliminating room effects, theory would say that asymmetric placement of two (or more) subs would have a better chance of being successful.  In practice, your patience, set-up skills, and EQ-ability would also be very important.
@auxinput,  I have already purchased batts of Roxul,  and some 1x3 select pine for the framing. Going to give that a go. 
Also, please excuse my ignorance here, but what does EQ stand for in this context . My thoughts are Equalizer, and Equipment, but I don't think I'm right. I have a lot to learn.
@musicjones - great!  Oh, another suggestion.  When you put together your panels, do NOT put a flat board on the backside (like a 1/4" plywood).  Any sort of flat board on the back will resonate and it will sound like a bad echo.  A 1x3 frame around the outside is just fine.
I was going to put a very thin cloth layer on the back side just to make a barrier between the insulation and my sheet rock walls . I do not know the correct term for it but I'm pretty sure the fabric store will have something along those lines