Facing a subwoofer towards a wall?

[SubAHolic]

Hello,

I have read some posts on this forum where others have mentioned that they placed their subwoofer driver/woofer facing a wall. So they may have corner loaded a sub but instead of placing the sub front-facing (where it's driver is towards the listening area) they have placed the sub where its driver is facing the back wall.

Are there any measurable advantages of this way of subwoofer placement? Thank you for your input in advance!

 

[BoredSysAdmin]

near wall, not facing wall. Unless it's your sub has been naughty

http://www.digitaltrends.com/home-theater/down-in-the-corner-tips-on-how-not-to-set-up-that-subwoofer-you-just-bought/

 

[shadyJ]

It doesn't make much of a difference if the woofer faces the wall for subwoofers. It may measure slightly different because the point of acoustic emission is maybe a foot or two away from facing a different direction, but that won't be a big deal.

 

[fmw]

If you want it facing the wall, that's fine although it may not look as nice as having the front face the room. Downfiring subwoofers, as an example are pretty common and they face the floor.

 

[SubAHolic]

Thank u for replies so far.

FMW: I am not planning on using it facing wall but was just curious since saw some posts where folks mentioned positioning the sub facing the wall. Honestly, it sounded bit strange to me as well but I understand that bass frequencies are non-directional.

Would also appreciate input from anyone who may have used the sub facing wall and can attest to any significant difference in performance.

Thanks

 

[mtrycrafts]

Thank u for replies so far.

FMW: I am not planning on using it facing wall but was just curious since saw some posts where folks mentioned positioning the sub facing the wall. Honestly, it sounded bit strange to me as well but I understand that bass frequencies are non-directional.

Would also appreciate input from anyone who may have used the sub facing wall and can attest to any significant difference in performance.

Thanks

No real need to do that especially if the two walls are more that 8 ft on each side, it is corner loaded.

 

[theJman]

Would also appreciate input from anyone who may have used the sub facing wall and can attest to any significant difference in performance.

Josh Ricci, the guy behind data-bass.com, always faces his subs into a corner. He swears by the advantages of doing that, so there's probably something to it.

 

[shadyJ]

Josh Ricci, the guy behind data-bass.com, always faces his subs into a corner. He swears by the advantages of doing that, so there's probably something to it.

His reason for doing so may be specific to his room. One advantage it may have is attenuating harmonic distortion, since many of those frequencies lay above the omnidirectional bass frequencies, although I don't know by how much. It might be an interesting comparison to test.

 

[Checker9]

Position toward listener does makes a difference (perpendicular to listener is more optimal all else equal.) I forgot the details behind it, but I read an article by some subwoofer designer (I think it was Mark Seaton but do not recall for sure) that advice not to point subwoofer toward the listening position (he named the type of cancellation it caused but I forgot the name), have them perpendicular to it.

Before reading that article, my subwoofer was facing me. It was already in the best place that I could find in my room (placed it via REW testing) but I had always placed it facing the listening area in all placements I had previously tested. I tested (measured with REW before and after) turning it 180 degrees so it faced perpendicular to my listening area, and it materially smoothed out a few areas within the frequency response in my room (the FR stayed close to the same, but some dips and peaks smoothed materially from how they were.)

Also, I think SVS stated that is why the Ultra tower speakers have the large woofer on the sides facing perpendicular to the front of the speakers.

 

[j_garcia]

IMO, it should face the longest leg of the room. The reason it may be affected by pointing it toward the wall/corner is you get an immediate reflection so rather than beginning to form and then hitting a corner, you get the immediate first reflection and then the wave begins to form. Since the wavelengths are so long, this may be an advantage. You also likely get some quick boundary gain.

Mine faces one driver toward the wall and both are perpendicular to my listening position, though it isn't along the longest leg of the wall - it still sounds best in this orientation.

In one of my previous reviews of a sub, it also sounded best when pointed toward the corner.

 

[Ricci]

I wouldn't say that I swear by it, but I usually do place them this way in most cases. What it does help with is smoothing the bass in the crossover region and the upper bass range. >70Hz. Works more effectively with bigger cabinets. Typically helps fill in one or two dips related to reflections from the driver to the wall/s and back to the driver position by placing the driver in much closer proximity to the boundaries so that this is pushed up much higher in frequency completely out of the bass bandwidth. Technically it may also help lower distortion a tiny amount as well.

 

[gene]

Hello,

I have read some posts on this forum where others have mentioned that they placed their subwoofer driver/woofer facing a wall. So they may have corner loaded a sub but instead of placing the sub front-facing (where it's driver is towards the listening area) they have placed the sub where its driver is facing the back wall.

Are there any measurable advantages of this way of subwoofer placement? Thank you for your input in advance!

Good question and yes there can be. I just added a 5th sub to my room and did just that. With the sub firing at the wall it did help with integration at the crossover region and most importantly made it less localizable. I will include this in my write up.

 

[alex30]

Here is what Josh Ricci had to say on the subject in a review he conducted for Audioholics :

I think we can probably trust his opinion.

 

[Checker9]

I wouldn't say that I swear by it, but I usually do place them this way in most cases. What it does help with is smoothing the bass in the crossover region and the upper bass range. >70Hz. Works more effectively with bigger cabinets. Typically helps fill in one or two dips related to reflections from the driver to the wall/s and back to the driver position by placing the driver in much closer proximity to the boundaries so that this is pushed up much higher in frequency completely out of the bass bandwidth. Technically it may also help lower distortion a tiny amount as well.

I actually tried it with good results. See my attached REW measurements. This is with a single PSA V1500 ported subwoofer in a ~1950 cubic foot room. I had the subwoofer near field for about 5 months but decided to try an original spot where I had it when I first got it. After Audyssey EQing, that spot produced a very flat response from 100 Hz to ~12 Hz, except a deep narrow band null. Same result this time, so I tried moving the subwoofer a foot or so around the same area, but the null got worse or another null happened. I then tried turning it 180 degrees where it faced straight into a wall but at the same spot otherwise. The non-EQ REW measurement looked promising. It looked the same as the non-EQ result from the same position but facing into the room, except when facing the wall, the same null was more shallow and more curved versus the sharp V shape of the null produced when facing into the room.

I then calibrate it with XT32, and the REW measurement was very nice, pretty much +/-3 dB from 100 Hz to around 12Hz or so (see attached graphs.)

Here are graphs of subwoofer only measurements with subwoofer facing the wall (about 5.5 inches from front baffle to wall.)

Here is a graph of the subwoofer in the same position except 180 degrees around facing into room:

 

[DukeL]

My subs are designed to have the driver face the wall. The reason is, I hate making grills, and that way I can get away with not making them. Since I don't have amps or anything else on the "back" of my subs (their amp goes on the equipment stand), I can get away with it.

When the woofer cone is within an inch or two of a room boundary, there is a modest increase in effective moving mass from improved coupling with the air, slightly raising the Qts and slightly lowing the Fs, which together will boost the very low end a little bit relative to the rest of the spectrum. We get that benefit without the effects of cone sag that a downfiring woofer would be subject to (yes I know cone sag is theoretically of negligible significance in most cases, but I'm not sure whether that would still hold true after many years of use as the suspension system softens up).

I don't see an obvious advantage to woofer-facing-the-wall as far as room interaction goes, nor do I see an obvious disadvantage either.

 

[shawnlim]

My subwoofer has a built facing down on the floor.
I mean the reflex port and the woofer itself.
So I guess facing wall should be fine as the sound will get reflected from the wall?