April 6, 2011

The Road to Surround – Part 6: The trigger to the surround sound field - dissatisfaction is a new dynamo!

By. Mick Sawaguchi

In the middle of 80's when my effort in the mixing of the radio drama got stable, my frustration gradually gathered in the fact that there existed a limit in expression by all means in the stereophonic sound field setting. The reason is because there were in radio drama a lot of elements such as mysterious profundity, an image, a spectacle and the inside of a person whose content cannot be realize unless expressed by an imaginative sound. The forerunning seniors used a medium called the tape making the most of it to express various processing composition a la musique concrete through the combination of pitches, tones, acoustics and phases.
In the Sound Department of our R&D Center, they had a working model of "sound field expansion device" which could widen the horizontal plane of a sound source to around 180 degrees by manipulating the phase, and also appeared were digital processing units such as RSS of Roland and 360-degree sound-field panning processors from some foreign manufacturers in those days.

An encounter with Dolby Stereo
Such tools were able to expand the sound-field from front to side by their panning processing and sense of openness. However, when I wanted to realize a panoramic sound-field of 360 degrees, I came to think about the need for some different techniques. An encounter is always a mysterious bond indeed. Mr. Saito then at Far East Continental in charge of cinema sound equipment distribution suggested that Dolby Stereo for movies might be applicable and that I speak to Mr. Fushiki who managed the software business.
At first I asked what Dolby Stereo looked like. A 4-channel master of front L-C-R and the monaural rear S will be encoded in 2-channel called Lt/Rt to be recorded and transmitted, and the technology approximately restores the original 4ch when decoded in the reception side.
As for the Dolby equipment for movies, they were well lined up in those days, and the price was considerably high, and the sound souce was targeted for optical recording on film, therefore it was impractical applying it to the broadcast production with the video basis.
Dolby was examining the expansion from film soundtrack to video and broadcast area, and the proposal was if we were interested in testing the small encoder/decoder called VE-3 for video and broadcast purposes the prototype of which had just been completed, so I decided to test it. After that, I obtained reference books about the principle of Dolby Stereo and its application, borrowed demonstration video tapes to watch, and the days passed until I found an opportunity for some suitable program to experiment.

The first step forward
In 1985, High-Vision VTR of analog specifications already existed, and various High-Vision test programs were produced with this format. Considering the fact that the audio of these VTR programs was 2ch only, we thought that combining multichannel surround sound with superb video would be attractive as a High-Vision program, and decided to apply this to a visual image program called "Autumn Kyoto".

Picture 1, Report of experimental program "Autumn Kyoto", 1986

Picture 2, Production system diagram

Which studio can serve us? CD-807 postproduction studio built in 1982!
It was the memorable facility for me as I updated the equipment, and because it had a Neve console with 4ch output, this seemed to be usable. Regarding why it was necessary to have the 4ch output then, I needed to look back toward the method of the postproduction facilities using MA-VTR in those days. The point was in the fact that we had to deal with two systems, a monitor bus and a recording bus for stereo. To the generation of current DAW, it is already the system of ancient days. While we had some 24-ch multi-recorders, questions continued about the monitoring environment, what kind of setting, necessary preparations and so on because everything from top to bottom for us was the very first attempt, and a temporary surround environment was built with the support of Mr. Mori and Mr. Fushiki of Dolby. As for the speakers, Mitsubishi standard monitor for front LR, Mitsubishi small-size, powered broadcast monitor for the center, and BOSE 101X4 for surround were used, which was almost jaw-dropping environment if compared to today’s stnadard. Mr. Suzuki with abundant drama experience was assigned as the mixer. All the staff had 2ch stereo experience but never with the surround, but the program was managed to be completed. I had surround reproduction setting installed in the preview room CA-412, and had people hear it. Being matrix surround, it was true to see some demerits in comparison to discrete programs as some people pointed, but the dominant reactions were the opinion that the immersive spaciousness in contrast to front-only stereo sound-field indicated a significant potential in the way of utilizing it with the big screen like High Vision. This was how the first step started.

Picture 3, The front monitor setting in CD-807 studio

Picture 4, Surround monitor setting in CD-807 studio

Picture 5, Production audition in CD-807 studio

Learning from forerunners of the movie sound
In the exhibition of audio engineers' organization called AES taking place in U.S.A. and Europe, there were presentations regarding the movie sound trend and discussions of techniques, and I decided to participate as it helps my study of English, too. When I visited related booths, there were a number of documents and booklets that seemed very instructive to read. They were not merely for publicizing the products of their own company, but explained the history of movie sound, the principle and application of Dolby Stereo, and actual examples of production.
In the workshops, presenters from the industry related with movie sound carried out practice of the surround sound production with demo and explanation. The most pleasant memory of mine was the session by Ben Burt who did the sound design of Star Wars (the first movie). He was introduced by the moderator, and came on the platform with full of applause. There in his hands were a stereo Nagura recorder and a stereo microphone running! And his first utterance being seated was "I was able to record the splended handcraps of all of you just now, and it will be a great piece of my library" which was received with a wave of cheers.
I could understand the content of seminar by only about 30%, but the atmosphere of the place where professionals gathered from all over the world was so exciting. It was this time when I had my determination to not only participate a session as an audience but to stand up some day in the opposite side to talk to the audience from the stage.

I was introduced by a senir to Mr. Segawa who promoted surround mixing then with movies positively in the country, and heard a story about the situstion of surround production in the movies. There were very few surround productions going on in Japanese movies, and the time in those days was when there were only few mixing engineers who had the know-how of the surround in the movie sound. Because Mr. Segawa had experienced co-production even in Hollywood, I was able to hear valuable experience from him. What was unexpected in his words said "even if you think it surround, all the sounds are not necessarily recorded in surround. Particularly in matrix methods, in order to prevent unstable localization, they use monaural sound source for ambience and the sound effects to construct them into total surround sound-field." It is because we imagined that surround recording was an extension of stereo recording and therefore assumed that there would be some miking and recording equipment specialized for ambient surround recording.
However, I understood the meaning of his words for the first time in 1987 as I had a real experience of a matrix surround production. That was it! In the matrix method, the sound-field and the localization were determined by the parameter of reverse phase and channel level difference. Therefore if ambience sound recorded in stereo is used in front channels, reverse phase ingredients included in the above source are detected, and flow to the rear channel unintentionally, which is phenomenally called "MAGIC SURROUND". Sound designers in Hollywood positively used monaural sound sources without such phase information to prevent the flow and created the spacious sense by putting them together! It took me several years to realize it.

Picture 6, from a production plan of High-Vision project proposed in April, 1987.

Picture 7, Examples of documents about the surround production that were released in 80-89

For the main broadcast realization - countrywide pilgrimage
The next subject after being charmed by sound expression in surround was the desire to apply it in a real broadcast rather than an experiment. Regarding this, it cannot be realized only by a single person, and the challenges come to my sight such as "how is the surround sound attractive?", "no problems to the present it to stereo listeners?", "how can the production resources develop in future?", and after all "how to propose a possible mixing room that supports surround production, not merely stereo as a facility to friends in sound business and production staff including your boss?". Under such circumstances, what we executed at first were surround experience demonstrations and seminars. For this, I had arranged equipment and a complete set of demonstration sources in cooperation with Mr. Fushiki of Dolby, and started my pilgrimage from the south in Fukuoka, the middle in Osaka, the north in Sendai and further to Sapporo including NHK Broadcast Center carrying the stuff. It was Mr. Imashiro of the Osaka technology camp and Mr. Hoshina, director of the radio drama to have agreed to my idea commenting "this offers interesting possibilities". By the enthusiasm of such people, a radio drama "Travel of Shuna" in 1987 and "Summer Koshien National High School Baseball Championship live broadcast" in 1988 by Osaka went on the air throughout the country.

Picture 8, Snap shot of a surround demo in Osaka in 1988. (How young I was!)

Next time, I will discuss the whole story of facility installation in the postproduction studio accommodated for surround programs targeted to become the home base for surround productions and also my experience in the early stage program productions.

2006.6 Broadcast technology

Part 7: Let's build a surround studio! >>>

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