Systemic Development > Bipolar System Disorders

How Does Incorrect Subwoofer Phase Manifest Itself?

(1/1)

James Edward:
As you can see from my equipment list, I use a sub…
As I can’t help but mess with things, I went looking for something, anything, to mess with today. I thought my initial setting of 180 degrees was right. This was even though the sub is up front behind my left speaker, which common thinking would indicate 0 degrees.
I switched it to 0 degrees, and I am hard-pressed to hear a difference.
Is there a definitive test for this? I think I remember reading that recordings vary in phase, so it may not be definitive from recording to recording. Or was that polarity?
Talk me down.
Thanks,
Jim

_Scotty_:
James your Spatial Audio M3 Turbo S are dipole loudspeakers, which means that the rear output is out of phase
with the radiation from the front. If the main loudspeaker produces any low frequencies, those emitted from rear of the speaker are out of phase with sub if it is at zero phase.  If the sub is set at 180 degrees, then the subs' output and the rear wave from the main are out of phase with the front and both are working together to cancel out the bass output from the front of the loudspeaker.  You can chose which side of the main speakers bass output you wish to try to reinforce with the sub.
 Every set up and room are different from each other, there may be no perfect setting between the subs phase and the main speaker.
All you can do is chose the one that you find most satisfying. If you can experiment with how far the mains are placed away from the rear wall and how far the sub-woofer is behind the plane the main loudspeakers you may
find a happy medium.

steve:
Hi James,

As a suggestion, I would play different musical selections along with different placements of the speaker for
the best midrange/highs. Once that is accomplished, I would connect the sub(s).

I would also include signal sweeps, say 500hz to 20hz, and see how each sub position and polarity reacts.
I would think that there might be larger bass mode(s) with one polarity than the other, or you might perceive
a dis-jointed quality with the "wrong" polarity. I am particularly wondering around the speaker to sub crossover
frequency. Maybe a double peak/dip.

I think the key is speaker position first, then work with the sub position and polarity.

Just a thought that might help James.

steve

steve:

--- Quote from: steve on June 23, 2022, 07:51:37 PM ---Hi James,

As a suggestion, I would play different musical selections along with different placements of the speaker for
the best midrange/highs. Once that is accomplished, I would connect the sub(s).

I would also include signal sweeps, say 500hz to 20hz, and see how each sub position and polarity reacts.
I would think that there might be larger bass mode(s) with one polarity than the other, or you might perceive
a dis-jointed quality with the "wrong" polarity. I am particularly wondering around the speaker to sub crossover
frequency. Maybe a double peak/dip.

I think the key is speaker position first, then work with the sub position and polarity.

Just a thought that might help James.

steve

--- End quote ---

Navigation

[0] Message Index