Virtual Audio is a new process of encoding audio in three dimensions,
passively or interactively. Virtual Audio requires no special decoding equipment
and provides a very accurate model of our hearing process. Virtual Audio
is so accurate that the listener cannot distinguish Virtual Audio recorded
sound from reality. Playback can be experienced on stereo or surround speakers
or standard headphones.
The Selective Hearing Process:
In the field of audio, the selective hearing process is fundamental to stress-relief. The selective hearing process in the human auditory system is the ability of the brain to tune into audio cues and tune out unwanted audio cues in the listener's environment. Selective hearing means listening only to audio cues that the listener wants to hear and not to those he does not want to hear, all at the same time. Sometimes called "the cocktail effect", the selective hearing process can be conscious or subliminal. When recording with normal recording technology, the selective hearing process is lost. The human brain can no longer selectively hear. The brain will try very hard to distinguish individual audio cues or try to break down the basic components of the audio cues, but will be unsuccessful. Normal recording methods do not encode the three-dimensional spatial cues necessary for the brain to carry out the selective hearing process . The brain will be unable to pull apart or selectively hear different component audio cues. The exception being that, if the volume of a specific audio cue is very loud, the brain will then be able to perceive the louder sound. Cues that are the same approximate volume will all blend in together.
Since the brain is trying very hard to decipher different sounds unsuccessfully, a type of stress is induced. The medium of standard audio technology itself actually induces stress.This stress will inhibit the listener from being emotionally involved with the audio cues optimally. With the use of Virtual Audio, the natural phenomenon of selective hearing is retained in the recording process.
Numerous audio cues that are moving in a sound field which has been recorded using normal audio recording techniques can become confusing to the brain since the listener cannot selectively hear specific sounds. When using Virtual Audio technology, the listener can selectively hear many sounds, stationary or moving without confusion. Sound encoded in Virual Audio enable the human brain to do what it normally does in nature: to selectively hear various component audio cues in the listening environment.
Virtual Audio encoded material inherently contains much more information to be processed by the human brain than normal audio. The result is greatly enhanced communication and emotional response from the recording when using Virtual Audio technology. When recording the sounds of nature or music, the use of the Virtual Audio process is very important, and in fact, fundamentally necessary for relaxation, meditation and the relief of stress.
The basic procedure of using the Virtual Audio Processing System (VAPS) in the recording process involves sending a mono audio source through a channel of the VAPS computer and then positioning the sound in a 360 degree space. Instead of the traditional panning of the left/right stereo field, VAPS allows a 360 degree panning capability. VAPS also allows the construction of each wall of a Virtual Room as well as the ability to locate those walls anywhere in a 360 degree space.
For the recording artist, producer or engineer, an understanding of the VAPS recording process is necessary for the best results. There are five basic levels of processing. At the higher level, a Virtual Audio environment can be created that is indistinguishable from reality. At the lower level, the result is Spatially Enhanced Stereo (SES) which has much more width, height, depth and clarity than the original stereo recording. Listed below, from elementary to complex, are the five levels of VAPS processing:
The first level of processing is called the SES Process. This process involves taking a two-track finished master and processing it through the VAPS. A two-track recording can be processed in such a way that the width is expanded past the stereo speaker field. The depth and clarity are greatly enhanced. Vertical information can be heard as well. The feeling of being immersed in a 360 degree sound field is presented on headphones. The exact translation of the sound field is directly proportional to the production characteristics of the recording. This process is very easy, fast and very affordable.
The second level of processing is called the SES Mix Process. This process is similar to the SES Process except it is done at the actual mix stage of the recording. The VAPS is placed on the stereo output of the mixing console before the two-track recorder. The advantage of this method is more precise control of the placement of each sound source in space. By having more individual control of each sound source, a more three-dimensional recording can be accomplished. This process is very cost effective for professional recording.
The third level of processing is called the SES Mix-Plus Process. It is a combination of the SES Mix Process and the Multi-Track Process (see below). The advantage of this method is that it still has the time and cost effectiveness of the SES Mix process, with the addition of three-dimensional room simulation and special effects such as sound moving around or over your head. The motion of individual sound sources are possible. The SES Mix-Plus Process is used for professional recording when special effects are desired.
The fourth level of processing is the Multi-Track Process. This process allows individual control of each sound source as well as three-dimensional room simulation for each sound source. The Multi-Track Process is the most advanced of the Virtual Audio proceses. It does require more time than the other levels since much more detail is possible when locating sound sources and designing virtual room spaces. Using this method, proximity effects can be created. Proximity is the effect of sound moving close and moving away from the listener. The Multi-Track Process is used for professional recording applications where the most control and effect in creating realistic Virtual Audio environments is required.
The fifth level of processing is the Virtual Audio Live Recording Process.
Using the Virtual Audio Live Recording Processor (a special type of artificial
head), live location recording can be accomplished simply and easily. The
recording is a complete 360 degree virtual recording of the actual event.
This process is used in live situations where the VAPS computer is not appropriate.
The live Virtual Audio recording, when utilized correctly, is quite impossible
to distinguish from reality.
Like the VAPS computer, Virtual Audio Live Recording is totally compatible on speakers and headphones. This method is very easy, convenient and is cost effective.
All levels of processing are completely compatible with each other. Any combination of these different processes will combine with each other without any artifacts such as phase shift or smearing of the audio image. All the Virtual Audio processes are compatible in mono. Although the Virtual Audio effect cannot be achieved in mono, the clarity and intelligibility of the sound sources are dramatically improved.
By understanding these different levels of processing, the end application and the playback medium (speakers, headphones, surround-sound systems etc.) will insure the optimum result using the VAPS computer.
Imaging is excellent, including depth and height whether playback is
in the usual equilateral-triangle stereo listening situation or in a narrow-stage
arrangement, such as loudspeakers flanking a television screen. Listening
area is wide, without sharp sweet-spot limitations.
A good approximation of a Virtual Audio presentation is available by using four loudspeakers: a front pair and a pair to the sides or behind the listening position. The second pair receives the same signals as the front pair, at a slightly reduced level. No signal processing is required.Headphone listening of Virtual Audio is excellent, and a complete 360 degree immersed sound field is obtained. Virtual Audio removes the annoying "in the center of your head" feeling that is common with headphones and exteriorizes all the sounds outside your head.
Mono playback is also not compromised due to the amplitude and phase flatness of the VAPS technology. Although the spatial quality is lost, intelligibility is greatly enhanced.
In the mix-down of several sound sources recorded on a multi-track recorder, VAPS can be used on every track to design a sound field particular to each sound source. These various tracks are then mixed down to a normal two-track stereo master. The master mix can then be used directly for CD recordings, video sound tracks, or stereo broadcasting on TV and FM radio bands. Home audio enthusiasts can enjoy an unsurpassed Virtual Audio environment on their conventional stereo headphones or speakers, hearing full reproduction of the artist's or producer's original intention. Another notable application of Virtual Audio is in the manufacturing of video and multi-media software for the consumer market. These products can offer Virtual Audio sound tracks which recreate the effects experienced in a movie theater with amazing realism. Further potential applications can be foreseen in a wide range of fields: Virtual Audio processing of conventional recordings and remixing for two-channel speaker reproduction; processing of video game sound; and processing of sampled sound sources for electronic musical instruments.
Currently Audio Cybernetics is offering the Virtual Audio process as a service. Audio Cybernetics will provide the Virtual Audio equipment at a daily rental with a trained engineer for your project. Audio Cybernetics can also provide expert consultation and full Virtual Audio production services.
Audio Cybernetics is currently developing a next generation, fully computerized,
three-dimensional, multi-channel, spatial audio processor that will fully
simulate the human auditory system. The system will also accurately simulate
acoustic responses of sound incidence to a given environment relative to
the listener, interactively and in real time. With these new tools, we will
be able to study psychological phenomena of sound in the human mind that
was previously not possible.
Give your next audio production the competitive edge of the latest In high technology! Virtual Audio!
Because of the high Definition of Virtual Audio, the web has not been the optimum place to deliver and show a real representation of Virtual Audio. Due to the tremendous sensitivity of the human ear, standard audio playback equipment cannot reproduce the full potential of the Virtual Audio technology. Of course the spatial character of Virtual Audio can be heard on almost any medium and will sound impressive but for the listener to have an audio experience which is indistinguishable from reality requires better audio equipment than most people have. The current state of the art of Virtual Audio is 24 bit at a 96KHz sampling rate. Some of the newer research has been in a 5.1 surround format with amazing results.
Due to the many requests for a Virtual Audio demonstration, Audio Cybernetics will soon make available a medium quality, stereo 16 bit 44.1 KHz sample rate Virtual Audio file for download. Please check back soon.