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Aperture details?

Spat
#1

Hi,

I have been having way too much fun with the perceptual controls and was curious if more details are available about what aperture is doing?

As is often the case, in forming my questions into words I have answered a few of my specific ones & come up with experiments to try to answer others - thanks! And I do look forward to any additional information as I am in my first few months of using SPAT.

Cheers,
Jimmy

#2

Here are the questions I still have:

-When I set a source aperture very narrow (10 deg), set yaw to 180 deg, and mute the room completely I can still hear the source, maybe 30dB lower than with yaw at 0 deg. Is this what should happen or is the signal leaking in from some other path?

-In the spat5.oper~ reference it looks like I can adjust the pitch and roll of a source as well, but I am not hearing or seeing what I would expect in terms of the interaction with the narrow aperture setting. Aperture is only visible in the xy view, is this a known issue?

  • When I adjust the pitch “/source/1/pitch $1” it has the glitchy effect of flipping yaw of the source between 0 or 180. In this case I was expecting the sound of tilting a directional source towards the floor or ceiling, is this possible?

thanks,
Jimmy

#3

Hi Jimmy,

-When I set a source aperture very narrow (10 deg), set yaw to 180 deg, and mute the room completely I can still hear the source, maybe 30dB lower than with yaw at 0 deg. Is this what should happen or is the signal leaking in from some other path?

That is the normal behavior. Indeed 30 dB attenuation is expected in that situation; that’s how the aperture/orientation model of spat works.

-In the spat5.oper~ reference it looks like I can adjust the pitch and roll of a source as well, but I am not hearing or seeing what I would expect in terms of the interaction with the narrow aperture setting.

Pitch is indeed supported.
Roll has – at the moment – no effect in our model.

Aperture is only visible in the xy view, is this a known issue?

It’s a known limitation. The display interface being 2D, it’s difficult to visualize a 3D directivity pattern.

  • When I adjust the pitch “/source/1/pitch $1” it has the glitchy effect of flipping yaw of the source between 0 or 180. In this case I was expecting the sound of tilting a directional source towards the floor or ceiling, is this possible?

That’s strange. I’ll investigate.

Best,
T.