Dual Sub Placement (1 Viewer)

[Chris Tsutsui]

lol.. Just because you aim your butt away from the person, doesn't mean they can't hear it.

I'm sure we all learned this lesson some time in our lives.

 

[Brett DiMichele]

Depends...

Was it a SBD or not? I mean really, to get an accurate
measurement we would first have to do an extensive DBT and
make sure the "levels" are matched...

 

[TimForman]

You guys should get together and start Flatulence Audio Research.
I thought it was the nature of "lower" frequencies to radiate more omnidirectionally than "higher" frequencies. Isn't this the cause behind "baffle step"?

 

[JoeFish]

The subwoofer radiates sound in a sphere pattern radiating pressure from the subwoofer driver

OK, I get this, and it makes sense.

Getting back to my original idea of speaker loading, and maybe this is a topic for another thread, but...

When I load, say a tube sub, in a vehicle, the subwoofer cone's proximity to a wall seemed to change the way the driver responded. Perhaps because of a reflex action between the moving driver and the hard surface. Has there been any discussion or theory on this type of loading?

-Joe

 

[TimForman]

Car audio is a different animal. It's almost like placing an enclosure inside another enclosure. I'm thinking the comparative application in home audio would be folded horn or bandpass type enclosures.

 

[Jeff_Sm]

Also take into consideration that if you stack your subs you have one sub elevated off the floor which will have the effect of evening out the floor/ceiling axial nodes to a certain degree whereas side by side would have the effect of evening out the side wall axial nodes.(also to a degree)

Of course it wouldn't alleviate them completely, but based on your room dimensions, one way could be better than the other.

I too have my two subs stacked in the corner and have had them that way for years.

 

[RichardHOS]

Drew,

I do realize that there is a fixed dB gain that will be present for all frequencies with corner loading, but as you clearly explained it is quite a bit less in the typical sized room than the theoretical maximum. If you are short on excursion or amplifier power (or both), then corner loading might be a necessity for that extra 2~4 dB. I'm afraid that some people might experience significant gains in SPL from corner loading though, and not realize that it is potentially a resonance problem that is creating that effect.

If "quantity" of bass isn't the problem, but rather the variability in amplitude response, as was the topic of this thread, corner loading may not be the best solution.

It all depends on your room dimensions, construction, acoustic treatments, and listening positions. I explicitly stated that in some rooms corner loading will actually give the most even response. That certainly isn't always the case, so I tend to think blanket statements like "put the sub in the corner, it creates the fewest nulls" is a bit oversimplified and misleading. In some rooms, if you are unfortunate to have closely grouped nulls with large voids between groups, a corner loading might result in the maximum number of nulls being created.

Remember, if you energize a resonant frequency in a room from the point where there should be a null, then you do not energize that resonant mode - there no longer exists a null at that frequency, for any position in the room.

Again, I think sub placement is something that should most often be decided on a case by case basis. If you had to guess at one location where the sub might sound decent, and would remain forever, I think the corner would be a safe bet. If you have the luxury and patience to experiment, a better position might well be found.

Of course, room treatment is still the preferrable option. In an ideal world, you could treat the room appropriately so that there were no nulls and peaks, even without equalization, no matter where you placed the sub. This would require extensive absorption of numerous offensive resonances. But, if done, then you could safely place the sub in the corner for that extra couple of db's without any fear at all.

 

[scott>sau]

Multiple subwoofers placed asymmetrically to yield smoothest bass response. Front left corner for number one, mid wall right for the second. Move the subs around the room to overcome exaggerated lower tones and standing waves. Use a RTA and parametric EQ to fine tune them. The key is experimentation.