December 31, 2006

Development of Broadcast Surround Sound Production in China 2006

By Eliten Cheng (Professor of Recording Engineering , AES member)

1. Introduction
Enjoying DVDs and home theater systems is a popular entertainment in China, so people are familiar to surround sound. There is Dolby authorized cinema in almost all cities even some towns. Surround sound in home starts in 80s with Dolby Logic Pro encoded Laser Discs, and now DVD with Dolby AC-3 or/and DTS encoded. , and are well-known surround sound film in China. Beijing Film Studio produced and released the first 5.1 format film named Opium War in mainland of China in 1997. The film uses Dolby SR-D system to sound production. In broadcasting systems, however, even though the radio stations have broadcasted FM programs in 2 channel stereo since 70s, but so far television sound still in monaural. In radios, few colleagues think about multi-channel broadcasting in end of 90s. But so far no any real progress I have heard.

2. HDTV demands surround sound production
As Beijing applied to be the host of 2008 Olympic Games successfully, therefore high definition television became a hot topic in China. The reason is that the live broadcast in Olympic Games must use high-definition television format. Recently China decided that Chinese HDTV has to be with multi-channel surround sound. Currently China Central Television Station (CCTV) in Beijing and Shanghai Media Group in Shanghai start HDTV broadcasting with Dolby AC-3 surround sound format in their pay TV channels. CCTV announced HDTV channel signal can be transmitted to up to 43 cities and towns after January 1st 2006, but local TV stations have to supply related transmitting networks and subscribers have to buy their own HD top-sets or HD TV sets at home for watching HDTV programs. There is big difference of development of HDTV between provinces. Advanced provinces and cities, for instance Shandong TV, Tianjin TV, Guangdong TV, Qingdao TV and Zhejiang TV etc, have equipped HD cameras and video systems. But they not all make the sound system in surround sound. Shandong television station has multi-channel surround sound live production and music master production equipments, later I will introduce in detail. Zhejiang TV and Qingdao TV use two channel stereo sound systems for their HDTV. Few TV station still buy analog mixing console for HD video and still in monaural sound system.
Even the question which format of surround sound will be used to HDTV? is still not final answer, but Orient Movie Channel of Shanghai Media Group has tried Dolby 5.1 TV broadcasting in June of 2004, and formally broadcast in June of 2005. At almost same time, CCTV decided use Dolby 5.1 to their HDTV pay per view channel. Therefore, CCTVユs HDTV set-top and/or TV set manufacture partners have to use same sound systems in their products.

3. Strong longing for study
Demanding on surround sound broadcasting, 2008 Olympic Games is not only reason. Due to people have their DVD player and home theater systems to enjoy surround sound movies, so they are not satisfied to current monaural TV sound which used more than five decades. They strongly hope TV programs can with stereo sound even surround as soon as possible. Meanwhile, some cutting-edge colleagues in television and radio stations begin studying multi-channel surround sound recording and production techniques. They are working for music recording, sports event reporting, entertainment live broadcasting and TV drama productions etc. They learn from magazines, books, Internet and audio equipment manufacturers (especially microphones) to get latest hardware information.

In the end of 90s, some large scale broadcast surround sound seminars hosted in mainland China. In these seminars AMS-Neve, Euphonix, SSL, Schoeps and DPA introduced their products and Mr. Andrew Munro and Mr. Sam Toyoshima explained their acoustic claim on recording studio design. But nothing helps to answer questions about how to do surround sound recording?and what is the suitable recording technologies to surround sound? by attendee recording engineers. Therefore, the cutting-edge engineers start their own discovery to surround sound recording in China.

In 2003, a Hong Kong based publishing company Technical Exchange Company - published a valuable Chinese version book - Surround Sound Recording Manual - written by Mr. Sawaguchi Masaki. This book soon becomes a very welcomed one especially by cutting-edge colleagues. They almost every one got a copy. We call this book as Surround Sound Recording Bible. Hence people know what are the DECCA Tree, Fukata Tree and Hamasaki Tree etc. People know surround sound recording can use in almost any events: sports, stage performance, large public gathering, airport, terminal station, storm, tsunami etc. And surround sound effect not only used in classic music but also in popular music and so on.

4. Take action
Chinese cutting-edge recording engineers can not wait for the answer, they read printed materials but more important thing is taking real action. In 2003, Mr. Lou Wei of China TV Drama Production Center replaced part of background music of original monaural musical TV drama - Fruit Girls by 5.1 surround sound. It became the first sample of surround sound TV drama in China. After this he completed a 2008 Olympic Games promotion video 2008 Beijing in Dolby AC-3. Now he made another TV drama Violin Solo . This time he not only uses music in 5.1 but also made all sound effects in surround. February 2004 in Beijing Exhibition Theater , Mr. Li Dakang of Communication University of China and Mr. Zhen Zhao of Beijing Film Academy did an experimental surround sound Chinese national music live production. They compared some recording techniques and post-production works and finally burned audio DVD in DTS and DVD-Audio format separately. Mr. He Bangjing of Guangdong TV is the first man he uses Dolby E equipments to his 5.1 surround sound live concert recording with video. The best one is Carl Oeffs Carmina Burana a live concert in Guangzhou Xinhai Concert Hall . Ms. Yang Qingqing of Shandong TV produced a documentary video Understanding Deng Xiaoping . She picked up many old recording materials and processed them into multi-channel to make 5.1 surround effects. This program makes colleagues and foreign guests very impressed. October 10th 2004, CCTV transmitted French musician Jean-Michel Jarr Beijing Forbidden City Live Concert to France directly in HDTV with Dolby 5.1 surround sound.

In October of 2004, I hold the first international surround sound hands on seminar in Guangzhou . Most of cutting-edge recording engineers to join this seminar, and invited world famous surround sound masters Mr. Sawaguchi Masaki from NHK and Mr. Andrea Borgato from Dolby. In this seminar foreign experts and Chinese engineers can discuss any interesting things face to face. This seminar lets China knows world, lets world knows China in this area. At this time Chinese recording engineers have jumped into a new stage.

5. Practice samples
Now I will introduce two sample sessions about broadcast surround sound production in China. One is an experimental Chinese national music live recording and post-production in February 2004, Beijing . Another is Spring Concert 2006 live broadcasting in December 2005, Jinan - the capital city of province Shandong .

5a. Live recording of a national music concert in theater
In early of 2004, my colleagues in Beijing plan to do an experiment. Before this they only know how to record western classic music in surround sound from books, but how use this knowledge to record typical national music stage performance is a big challenge to them. Do practice is only way face to cutting-edge engineers. This will be a creative step to surround sound national music in China.
Beijing Exhibition Theater is built in 50s. It was a hypaethral theater originally. Later 70s it is rebuilt to a round roof theater by Chinese acoustic designers and usages of the theater was expanded, acoustic effect has modified better. Beijing Spring Concert 2004 was performed in this theater. Beijing colleagues contacted the concert organizer to ask them if allow them to do surround sound experiment. The answer is positive, they allowed doing twice recording: one is rehearsal before official performance, another is live recording in restricted microphone setting conditions. The task includes two projects: a stereo recording for the concert organizer and an experimental multi-channel recording.
In the afternoon on 1st of February, recording staff installed microphones according to planning diagram. 2 sets of 3 meters high surround sound microphone stand were located on stage and audience seat place. Because these are special microphone stands, no existing product to buy in China. They have to design and make the stands by themselves. The theories of multi-channel surround sound recording are still not completed, the recording formats are still changing and discovering. So they have to do everything by their own, from draw design diagrams to manufacture and assembly these devices. They have no surround sound live mixing console, so use two smaller TASCAM DM-24 and link together as a bigger one.

Mr. Li Dakang of Communication University of China and Mr. Zhen Zhao of Beijing Film Academy are the planner and executive of this experiment. About the background and motivation of this experiment, Mr. Li said: As same as in last century 70-80s stereo replace monaural in record and FM radio, surround sound must replace current 2-channel stereo. This is a trend, no one can stop it. Now there are many successful surround sound recording techniques around world, but which one is most suitable to Chinese music (performance by Chinese music instruments)? How we improve? This is our Chinese recording engineerユs business, can not wait for foreigner to do for us. Mr. Zhen has his opinion: メI saw foreigners promote surround sound experiments very actively, we can not just wait and read and talk. People always avoid to meet unfamiliar or unsure things, however how can they change current situation and step forward? We must do something When they are informed that typical national music concert, they make the decision at once.
Whole experiment is large scale and complicated, they have to coordinate the staff (around 20) and equipments from 6 more companies. Mr. Li and Mr. Zhen made the recording plan and system configuration. Because the recording equipments must be installed in the audience area, so they can not use speakers to monitor only headphone allowed in location. It means only stereo can do live monitoring. For the final effect they decided to record more tracks on 4 sets of TASCAM DA-98 8-tack DAT tape recorder (total 32 tracks) and hard disks of a Pyramix DAW. They can do compare, production and mix-down later in their studio. And live stereo recording materials are for reference during producing surround sound and publishing CD of the concert.

Microphone configuration and system block diagram refer to Fig. 1 and Fig. 2.

Due to this live recording is an experiment, so recorded tracks are much more. We have to choose listening format then organize these tracks to listen. If not feel good, we will choose other tracks to replace. Every track have no fixed balance, you have to try one by one. If the effect is not good, may give us a wrong impress about these tracks, even loss confidence on our experiment. So join the post-production work not only Mr. Li and Mr. Zhen and their assistants, but also include Mr. Lou Wei , Ms. Kate Wu (Dolby Lab Beijing Office), Ms. Yang Qingqing from Shandong and I from Shenzhen . We listened every combination very seriously and repeatedly. Finally we choose few best combinations for movie, video and disc. We all have positive reaction to this experiment, the experiment is successful. We have strong environment feeling for movie and accuracy sound imaging and presence for music. We all have very deep impression to the experiment, because national music instruments can provide as wide and great sound field as western. It is unexpected before. The best combination of tracks mix-down to be master and burned audio DVD using DTS and DVD-Audio encoding. Copies of DVD are sent to colleagues in other cities for their assessment and opinion.

Above mentioned Beijing Film Academy and Communication University of China (former name is Beijing Broadcast Institute ) are very famous colleges in China. Most broadcast colleagues graduated from them. So that the success of this experiment promotes development of broadcast surround sound in China. More and more television stations adopt surround sound system for their HDTV studio after this experiment which is so-called remarkable milestone on surround sound live recording development in China.

5b. Live recording with video in a HDTV studio
In October of 2005, a HDTV studio of Shandong Television station was completed. In this new studio, a perfect multi-channel surround sound production system is deep impressed visitors. Main purpose of HDTV studio is for entertainment, gathering and column live broadcasting in door, so the function of audio system in it is more like as a PA system not master production. For high quality TV sound production, however, Shandong TV equipped Euphonix System 5 digital console, dynaudio-acoustics Air25 5.1 monitor speakers and Fairlight Satellite 4 DAW in audio control room of HDTV studio. These audio equipments are used in master production studios mostly. Remarkable thing is that Shandong TV bought whole sets of microphone. In spite of popular stereo microphone from Schoeps, DPA and Neumann, they bought Schoeps KFM360 sphere surround sound microphone.

With this HDTV system, Shandong TV has produced various live performance programs, a chamber concert and an orchestra concert so far. All programs have synchronized video and multi-channel audio materials in order to HDTV program storage for future. These programs have better quality than ever and with surround sound. Especially the Spring Concert 2006 , it is a live symphony orchestra concert and shooting by HD video cameras with totally surround sound microphone setting. Because this is the first time to do so large scale symphony orchestra (72 musicians on stage) recording in Shandong TV studio and must sync with video, so it is a totally different task and a big challenge to audio engineers. Ms. Yang Qingqing with her colleagues of this station began preparing a week ago before orchestra formally performance. According to the configuration of orchestra (standard double wind band) and performance works, they made an accuracy plan including surround sound recording method, equipments setting, microphone setting, system connecting and recording technology flow etc. On the stage there are Decca tree plus PZM, IRT, Schoeps 360 sphere microphone and so on. In addition, for solo, vocal solo and compensation points they provided suitable microphones separately. All together 30 more microphones were used. While doing video live recoding, all microphone input signals are separately recorded on to their own track on Fairlight DAW. Meanwhile live mix-down stereo signal pair is recorded on sound tracks of video recorder. Stereo signals are picked up by Decca tree and related compensation point microphones and trimming and balancing on location. The quality of completed stereo signal with video and the signal recorded on tracks along are satisfied. Even broadcasting of this concert is still in standard definition TV and monaural sound, but saving all program materials in high definition video and multi-channel audio. Later they organized these materials and do mix-down for surround sound audio master and use Dolby E system to record on HD video tape.

The microphone configuration refers to Fig. 3.

6. Conclusion
To replaces current standard TV by HDTV completely is impossible so far in China. HDTV signal transmitting and receiving equipments are still expansive to TV subscribers. And HD program storage is far not enough. So, standard definition TV and HDTV will exist in parallel for a long time. Based on this real situation when many TV stations buy their HDTV equipments they must think the compatibility. Now stereo audio equipments and surround sound equipments have no big price different between them. So most of them will buy surround sound audio systems directly.
But depending on recording engineers personal knowledge and skills, may start from stereo experiments. Few stations really less qualified engineer, so monaural sound is still continuing with HD videos. However, I believe this situation will be changed soon by TV broadcast marketing.

In mainland of China, the main TV stations have clear recognition to HDTV that is the audio systems must be multi-channel surround sound. In the other hand, because main businesses of a TV station are live broadcast (indoor and outdoor), so sports, entertainment performances, on location recordings use multi-channel sound recording techniques more and more. The cutting-edge engineers surround dream will come true.
Surround sound production for HDTV in Shandong television station is a successful sample in China. I believe that more and more TV stations will try their surround sound production and radio stations will develop their multi-channel programs.

7. Acknowledgement
Finally, I appreciate Mr.Mick Sawaguchi Masaki for his contribution of knowledge and experience to the world surround sound industry and my heartfelt thanks to him for giving me the chance to introduce to the development of broadcast surround sound in China.

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