> A linear polar plot, with the concentric circles usually labeled somethin=
g like "1, .8, .6. .4, .2", shows the real shape. On a linear plot of a car=
dioid mic you can see that 90deg incidence is .5 sensitivity. I think Sennh=
eiser was the last to use linear plots, but now they follow the crowd in st=
andardized stupidity.
>
Hi Dan,
I agree the linear plot would be more useful when applying to distances. Ma=
ybe we can estimate a linear plot by taking the difference in sensitivity b=
etween on axis and off axis sounds and divide by two for each drop of 6dB =
- therefore -6dB will be .5, -12dB will be .25 etc.
The converted polar pattern might then reflect the effect on sounds at dist=
ances. It might also be useful to translate that polar sensitivity plot int=
o contour curves that show the steepness of perceived distance compression =
for a soundscape. The contours would be practical distance intervals. This =
would look somewhat opposite to the polar plot as the on-axis distances com=
press closer together or the off-axis sounds expand into the perceived dist=
ance.
John Hartog
rockscallop.org
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