I am going to record an Opera-Singer for a surrealistic short-film a friend of me was shooting earlier this year. After the recording i am trying to move her voice in postproduction trough a 3-Dimensional space fitting to the pictures.
Things to think about:
What is the perfect microphone Setup?
As 3D sound tools use mono-sources (or render stereofiles down to mono), i am aiming for a simple big membrane setup. The situation doesn`t allow me to visit a proper recording room, so i am going for a little bit of an DIY approach. Some Rugs and blankets will be used to treat the room for achieving the clearest signal possible.
The scene:
As seen in the picture the scene starts in a (virtual) room
How to move the object?
I spent a long time searching for the perfect tool to move the voice through the percepted virtual 3D-Space AND keep the file in stereo as the movie will only be mixed down in stereo. In all the tests i did the Plug-In “DearVR Micro” from DearVr in collaboration with Sennheiser did in my point of view th best job (and it`s for free yey!).
As the film will be surreal im am aiming also for a surrealistic sound design. The first issue im thinking of will be the transition from the virtual “inner” room to the outside.
The recording took place in an (as mentioned above) empty, roughly 20m2 big room. As you probably can imagine the reverberation was pretty huge, so i had a little bit of an “MacGyver” – attempt to get a clean recording. With the help of 6 tripods, 4 bamboo sticks and loads of rugs an other textil i created a capsule and achieved some honestly not too bad sound. In thoughts of my hopefully future career i wont show a picture.
As the record worked well, i will move on to the post processing. Stay tuned!
Binaurale Ansätze für räumliche Sounddarstellung basieren auf der Idee, dass die beste Reproduktion von natürlichem räumlichem Hören dadurch erreicht wird, dass die Ohren der HörerInnen mit denselben Signalen versorgt werden, welche im ursprünglichen Aufnahmeort während des natürlichen Hörens auftreten würden.
Im besten Falle zielt die binaurale Technik dahingehend, alle räumlichen Marker im Sound wiederzugeben die benötigt werden um ein räumliches Wahrnehmungserlebnis bei HörerInnen zu erschaffen. Verschiedenste Faktoren wie die Position und Form der Ohren, Form des Torsos und Ausrichtung des Kopfes spielen hier eine unmittelbare Rolle. Ohne spezielle aukustische und psychoakustische Effekte ist die Wiedergabe vorerst nur über Kopfhörer möglich, da bei ihnen pro Ohr jeweils ein Channel übertragen wird. Diese Separation der beiden Channel ist sehr günstig für die Wiedergabe von binauralen Stereoaufnahmen da sich die Kanäle in Timing und Amplitude, ähnlich dem Abschirmungseffekt des Kopfes, unterscheiden können.
Die Idee, Sound genauso darzustellen wie er normalerweise gehört wird lokalisiert sich historisch unmittelbar am Beginn des Audio-Universums:
Im Jahr 1881 installierte der französische Radio- Luftfahrtpionier Clement Ader, zum ersten Mal in der Geschichte zwei Mikrofone an der Bühnenkante der Opera Graniere und leitete das Signal über Telefonkabel zu HörerInnen, welche in einer Telefonkabine zwei Kilometer entfernt warteten. Das sogenannte „Theatrophon“ zog rasch die Aufmerksamkeit europaweiter Theater auf sich und so wurde auch Menschen außerhalb des Theaters die Möglichkeit der Unterhaltung geboten. Da es sich um 2 getrennte Mikrofone handelt, welche jeweils die Signale diskret an jeweils ein Ohr weiterleiten, spricht man hier von der ersten binauralen Erfindung.1
Etwa 50 Jahre später wurde “Oscar” zum ersten Mal der Öffentlichkeit vorgestellt. “Oscar” ist ein Dummykopf dem auf auf jeder Wangenseite ein Mikrofon eingebaut wurde. Für das Projekt war Harvey Fletcher verantwortlich. Fletcher wird wegen seiner Experimente mit räumlichem Hören in der 1930ern auch oft als der „Vater der Stereofonie“ 2 bezeichnet.
1. “Oscar” und Harvey Fletcher 1933
Es dauerte beinahe weitere 40 Jahre bis das Konzept der binauralen Mikrofonierung den Weg in die Kommerzialisierung fand. Mit KU-80 brachte die Firma Neumann das erste binauralen Kunstkopfmikrofon für die breite Öffentlichkeit auf den Markt.
Lou Reed nahm 1978 mit “Street Hassle” das erste binaurale Album der Geschichte auf.
I was gathering Informations about some really use- and powerful 3D Audio Software.
1 Sound Particles
Sound Particles is a sound design software application which creates a broad number of sounds in a virtual 3D audio world.
SP basically uses the concept of computer graphics, but for audio: each particle represents a 3D sound source (instead of a 3D object) and a virtual microphone captures the virtual sound of the particles (instead of the virtual CGI camera).
Imagine that you want to create the sound of a battlefield with Sound Particles. You could create 10.000 particles (sound sources), spread them over a square mile, pick 50 war-related sounds from your sound library and render the entire scene with a virtual microphone (5.1, Dolby Atmos 9.1 bed, etc.). Each particle would randomly select one of the war-related sounds for reproduction, which means that some particles would reproduce the 1st audio files, other particles would reproduce the 2nd audio files, and so on. Also, each particle (sound source) would be positioned randomly on a square with a length of 1 mile. To obtain more interesting results, movement modifiers would add motion to the particles and audio modifiers would apply random gains, delays, EQ or time/pitch variations. The virtual microphone will be responsible for capturing the virtual sound of the scene, based on its position, direction and the position of all particles. The sound of all particles is rendered, taking into consideration things like propagation attenuation, speed of sound and Doppler effect.
The Outputformat ranges from Stereo up to immersive audio formats, such as Ambisonics, Dolby Atmos, Auro 3d and much more.
There is also an free educational license available.
2 Die Benutzeroberfläche im klassischen Ableton-Stil ist sehr intuitiv zu bedienen.
Envelop4Live is used for the spatialization of immersive sound in all Envelop listening spaces, yet it can also work with any DIY speaker array (4 speakers minimum) or even normal headphones. E4L creates an open and accessible path for artists, producers, and designers, to create immersive audio and explore 3D music composition.
As described above Envelop offers different Venues (virtual and “real” ones) where your compositions can be reproduced. https://www.envelop.us/venues
Envelop also created other very convenient tools for Higher Order Ambisonics like “Earshot” an “EnvelopLX”:
.Earshot is a free and open-source transcoder for live streaming Higher-Order Ambisonics. Using Earshot, spatial audio developers can build new and innovative immersive live experiences for the web. Earshot solves the problem of getting audio or video content with non-standard audio channel configurations (i.e., beyond stereo or 5.1) from a source computer to the browser. It is based on nginx, MPEG-DASH, and the Opus codec which supports up to 255 audio channels (or 14th-order Ambisonics.)
.EnvelopLX is an interactive lighting application used within the Envelopvenues. It runs in Processing using the LX Studio framework. The system may be controlled directly, or via remote OSC control from Envelop for Live devices, which can be composed and sequenced within Ableton Live 10. Real-time spatial audio metering and position data can also be used to control animation.
Halo is basically an up- and downmix plugin for 5.1 and 7.1 speaker configuration. Nugen also offers the 3D Audio extension, which can upmix also Atmos and Ambisonics.
“Halo Upmix delivers all the control you need to fine-tune your surround mix to perfection. With unique centre channel management, including switchable dialog extraction, Halo Upmix is perfect for all types of production from archive restoration and TV through to the full 7.1 feature film experience.
An optional 3D extension adds Dolby Atmos bed track (7.1.2) and Auro 3D (7.1.4) compatibility, and Ambisonic outputs.”
“The optional 3D Immersive Extension introduces additional vertical controls via an expanded user interface including control over Ltm and Rtm placement for Dolby Atmos compatibility. An additional real-time analysis view is also included for the vertical dimension, showing energy distribution of the output audio. The enhanced upmix algorithm allows for simultaneous use of all the original features including dialog isolation and individual channel output control.
The 3D Immersive Extension is suitable for numerous applications including sound design, film score, restoration & archive, music and atmospheric soundscape production.”
With a price about 600 Euros this tool is definitly more for professional studios than home users.
Enjoy new creative mixing possibilities in a full three-dimensional space far beyond the reach of a simple stereo panner. dearVR MICRO enables you to position signals in any location left, right, above, below, in front or behind your head – instead of only left or right.
The parameters Azimuth and Elevation give you control over the horizontal and vertical position of your audio source in degrees. Adjust the perceived stereo width of your stereo sources in the three-dimensional space using the width knob.
DRVRMico also contains 3D binaural Room reflections and HRTF – Rendering.
(free) dearVR AMBI MICRO allows sound engineers to mix, monitor and render Ambisonics tracks right out of the box. With support of higher order Ambisonics formats as well as multiple binaural output monitoring (i.a. Facebook360 and YouTube VR) it is an all-in-one solution for 360° Video and VR productions. Encode Ambisonics signals with dearVR PRO, mix with dearVR SPATIAL CONNECT and monitor head-tracked with dearVR AMBI MICRO.
Create ultra-realistic acoustic environments in Unity with a true perception of direction, distance, reflections, and reverb. dearVR UNITY, tested as the number one spatializer plugin for Unity with the best sound and the best externalization, offers positional 3D audio and true-to-life acoustic room virtualization.
dearVR FMOD seamlessly integrates with your Unity or Unreal Engine project, giving you highly accurate spatialization of a large numbers of sound source. Adding ultra-realistic acoustic virtualization and phenomena like occlusion and obstruction gets you a fully immersive user experience.
Anaglyph is part of an ongoing research effort into the perceptual and technical capabilities of binaural rendering. The latest incarnation, Anaglyph VST, has been designed as an audio plugin to both support ongoing research efforts as well as to make accessible the fruits of this research to audio engineers through traditional existing DAW environments. Amongst its features, Anaglyph includes a personalizable morphological ITD model, near-field ILD corrections and HRTF parallax selection, a Localisation Enhancer, an Externalisation Booster, and SOFA HRIR file support.
