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Under the hood of Panoramix

panoramix
#1

Hi Thibaut,

I am currently working to control Panoramix from an iPad (via Mira using OSC) and find many previously (for me) unknown treasures to explore.

One of them being the azim++, elev++ and dist++ methods, that works equally well on sources, channels and beams - quite pleasant !

A few questions:

  1. Focus on HOA streams or Bformat tracks seem to have one single beam (no matter what order). Why is that when HOA busses can have any number of beams?

  2. I am exploring spatialisation of channels on a multi track. Direct gain seem quite loud (when linked to distance) if sources are centered. I have tried to unlink and to downscale direct gain, but I find it remains quite loud at the center. Where can I find out how direct gain, early gain and reverb gain are calculated in relation to distance? I would like to make a version that goes a bit softer with these gains.

  3. Inside Panoramix (or spat) I am looking for something that can controll gain of individual sources or channels (not the track gain). So far I only found the channels gain correction (which must be switched to “manual” in order to work). Are there other or better ways? What method do you recommend?

Sorry for the mixed nature of these questions. I hope its ok to bundle them here. Kindly Hans Peter

#2

Hi,

1. Focus on HOA streams or Bformat tracks seem to have one single beam (no matter what order). Why is that when HOA busses can have any number of beams?

Well, that was a design choice, for the sake of simplicity.
You can have multiple beams on the HOA busses.
If you need something more “precise/customizable”, then you’d have to use separate spat objets (spat5.hoa.beam).

2. I am exploring spatialisation of channels on a multi track. Direct gain seem quite loud (when linked to distance) if sources are centered. I have tried to unlink and to downscale direct gain, but I find it remains quite loud at the center. Where can I find out how direct gain, early gain and reverb gain are calculated in relation to distance? I would like to make a version that goes a bit softer with these gains.

“Multi” tracks are really just the same as several “Mono” tracks combined together. So, gains should behave similarly.
Direct gains follows a “-6dB law” i.e. the level decreases by 6dB when doubling the distance (going from 1m to 2m ==> -6dB; going from 2m to 4m ==> -6dB; etc.)
Early and reverb laws are not disclosed.

You may also use the gain “offset” associated to direct/early/reverb gains, if needed.

3. Inside Panoramix (or spat) I am looking for something that can controll gain of individual sources or channels (not the track gain). So far I only found the channels gain correction (which must be switched to “manual” in order to work). Are there other or better ways? What method do you recommend?

Do you mean controlling the level of independent output channels ?
I dont really have any recommendation for that; although you could do it with the per-channel EQ available on the Master strip.

Hope this helps,
T.

#3

Thanks for detailed response!

  1. OK. I believe having multi beam on busses makes sense since busses combine several tracks (that might need some aid when combined) whereas a track generally relates to a single source. Multi beams for tracks could potentially make sense when you want to enhance several “spots” in a HOA recording (e.g. em32). Thanks for pointing to Spat5.hoa.beam for these purposes - a great object!

  2. I see. I believe my problem is inside the last meter where gain grows quite a lot. Imagine I find outside the 1 meter fine, but inside too loud, will offset not be the same no matter the distance? If I only want to correct gain inside the magical 1 meter?

  3. I was actually thinking of a gain for sources at the track level. Between input and output. I found gain correction in channels… which seems intended for adjustment of the relation between inputs. I was not aware of the per-channel EQ on the master. Also great even if not quite what I was looking for.

Kindly Hans Peter

#4

Hi,

  1. Yes offset would be the same no matter the distance. If you want a specific gain curve (with specific behaviour inside the ‘magical’ 1 meter zone), then you’d have to implement that curve yourself, by sending the appropriate gain messages to Panoramix.

  2. Still not quite sure to understand precisely which gain you’re trying to control. Track gain can be adjusted in several places: ‘trim’ dial, ‘direct gain’ dial, gain for each bus send, output gain of the track strip, input gain of the corresponding bus strip, etc.
    If you’re trying to independently adjust the gain of each channel of a “Multi” track, then it’s probably easier to just replace that “Multi” track with several “Mono” tracks.

Hope this helps,
T.

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