Directionality of instruments in MIR

[Adrien]

Hi

sorry if this has been asked a million times before.

I'm trying to figure out what direction things are in relation to the shape of the ellipse in MIR.

For something like a trumpet, of course you expect the sound to come shooting out the front.

For strings and especially string sections it's not at all clear.

If anything a violin shoots sound out the side (the bow-arm side).  Celli shoot forwards directly towards the conductor (not out to the audience) if they are on the standard RHS of the stage (from the stalls).

So do we point the instruments in the direction we believe the sound goes.  Or does the radiation pattern baked into the instrument take into account that the instrument may be side-firing?

Thanks again

Adrien

[Adrien]

Actually the shape of a section of violins is never an ellipse either.  It has both depth and width.  Same with other sections.

[Dietz]

Hi Adrien,

that's a valid question! It should be answered by the section of MIR Pro's manual called "Think MIR!", or more specifically the paragraphs explaining MIR's Instrument Directivity Profiles.

The ellipse around MIR's Instrument Icon is just an indication of the relative stereo with of the input signal and has nothing to do with ist directivity.

HTH,

[Adrien]

Hi Dietz

thanks, I read that section, but it doesn't show me how I can see the radiation pattern of an instrument to know whether the direction line is the direction of maximum output, or whether it's the way the player faces when playing.

I guess I could put an instrument in an anechoic chamber (is there one in MIR?) and rotate it to see if I can hear the difference.

[Dietz]

MIR Pro takes care for all of that. :-)

There is no actual display of the radiation patterns, but you can see exactly in which direction the player is looking on stage just by means of the Instrument Icon: The volume handle is also the 0° direction pointer. We talk about it as "the player's nose". 8-)

If you want to hear the effect of the directivity filters in a virtual "anechoic chamber", set MIR Pro to Dry Solo and activate the option for "Directivity Filtering" for the dry signal. - Usually, directivity filtering which is only applied to the signal sent into the convolution core, depending on the data stored in the Instrument Profiles and the rotation of the Icon. By activating this option, also the dry signal will be filtered when you rotate it. - The perceived effect is pretty much the same as the player would turn the instrument away from the spot microphone. This (virtual) spot mic will stay in its perfect relative position as long as the option is switched off.

HTH,

[Adrien]

OK

so the line is showing which way the player is facing, rather than which way the sound is radiating?

So for 1st violins it should be pointing to the mid-front of the stage, rather than pointing at the audience, same with celli?

Sorry, just want to be clear it's to do with seating rather than sounding.

[Dietz]

@Another User said:

So for 1st violins it should be pointing to the mid-front of the stage, rather than pointing at the audience, same with celli?

Sorry, just want to be clear it's to do with seating rather than sounding.

If you load (or just look at) all the MIRx settings you will get the idea how _I_ like to do it: Most of the time individual players will point indeed towards the Main Mic, while ensembles try to make use of as much of the signal-inherent stereo information as possible (thus you will see them stretched crosswise or diagonally):

-> https://www.vsl.info/en/manuals/vienna-instruments-mirx/venue-details/konzerthaus-grosser-saal (... just scroll down and/or use the navigation on the left side for screenshots from all seven "MIRx-ed" Venues).

... yes, there are cases when I found that departing from the obvious "looking at the conductor"-paradigm made more sense, soundwise. 😉