Andrey Kireev
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- Aug 25, 2026
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According ambisonic order guide, described all possible spatial patterns of polar patterns in 3D vision.
The 0th order is a sphere, exactly the same as an omnidirectional electret microphone, but not a condenser microphone.
The 1st order is two semicircles in a figure-eight cross-section, just like ribbon microphones. But first-order microphones are already a 4-channel microphone.
Second-order polar patterns are formed by stereo pairs, but are equivalent to a multi-channel microphone.
I don't understand why the order of ambisonic isn't equal to the polar patterns of microphones or microphone arrays.
In the picture above.
I see similar discrepancies in different places and articles.
P.S.
I asked this question on the diyAudio forum, but no one there had a right answer.
After some thought, I found byself this answer:
I think I'm beginning to understand the catch with the mathematical model.
The theory of spherical harmonics describes all theoretically possible models, without taking into account their application.
From the perspective of wave radiator theory, there are point and linear radiators.
But for acoustics, a linear radiator with equal potentials is impossible.
In acoustics, a linear radiator is a membrane that always has different potentials.
This means that some ambisonic models cannot be implemented in practice in the sound field.
The entire Ambisonics order should be divided by 2 to exclude inapplicable models. Maybe I'm wrong.
The 0th order is a sphere, exactly the same as an omnidirectional electret microphone, but not a condenser microphone.
The 1st order is two semicircles in a figure-eight cross-section, just like ribbon microphones. But first-order microphones are already a 4-channel microphone.
Second-order polar patterns are formed by stereo pairs, but are equivalent to a multi-channel microphone.
I don't understand why the order of ambisonic isn't equal to the polar patterns of microphones or microphone arrays.
In the picture above.
I see similar discrepancies in different places and articles.
P.S.
I asked this question on the diyAudio forum, but no one there had a right answer.
After some thought, I found byself this answer:
I think I'm beginning to understand the catch with the mathematical model.
The theory of spherical harmonics describes all theoretically possible models, without taking into account their application.
From the perspective of wave radiator theory, there are point and linear radiators.
But for acoustics, a linear radiator with equal potentials is impossible.
In acoustics, a linear radiator is a membrane that always has different potentials.
This means that some ambisonic models cannot be implemented in practice in the sound field.
The entire Ambisonics order should be divided by 2 to exclude inapplicable models. Maybe I'm wrong.
