In line with is remit to deliver a diet of news, documentary, sports, comedy, entertainment and drama programming across China, CCTV has been updating its operation and moving to a new facility Beijing – an iconic building designed by Rem Koolhaas and Ole Scheeren of Office for Metropolitan Architecture. Equipping its new HQ has involved additional equipment, including systems from TC Electronic and QSC.

At its former facility, the broadcaster has used TC Electronic DB4 transmission processors for audio processing for several years, so the upgrade to DB8 MkII units at the new location was logical. Here, CCTV has five identical control rooms, each of which is capable of handling ten TV channels. Two DB8 MkII units are used for each channel – one for processing and one as backup – meaning that there are 20 units in each control room, and 100 in total.

‘We have inserted the DB8 MkII units into the signal chains of our broadcasting system and use them for loudness measuring as well as real-time loudness correction and upconversion from stereo to 5.1,’ says Jiang Ming, Chief Broadcast Engineer at CCTV. ‘The units are used in live broadcast transmissions, so reliability is absolutely key. We used TC’s DB4 units at the old CCTV site for years, and they never failed. Another important factor is that we want to control the loudness of the programs we broadcast, but at the same time we do not want to sacrifice the audio quality. We brought in a lot of different processors and carried out comprehensive tests, and ultimately the DB8 MkII units performed the best.’

The DB8 MkII units are equipped with SDI I/O cards, and CCTV uses the ALC6 algorithm for loudness correction and UpCon HD for upconverting stereo signals to 5.1 plus two instances of the LM6 Radar Loudness Meter for measuring loudness at the input and the output stages. CCTV also makes use of the dual power supply feature, feeding the units simultaneously from two independent power sources to make sure the units can withstand a breakdown on one of the power feeds.

The units are controlled via the TC Icon controller software and a tailor-made solution has been installed for automatic per-program measuring and reporting of specific loudness descriptors. Finally, comprehensive SNMP trapping has been set up for system surveillance from the old CCTV site located 15km from the new facility.

Performance sound

CCTV has also installed a QSC KLA Active Line Array system in a 400-seater multi-purpose hall used for meetings, seminars, demonstrations, lectures and live broadcast. The installation comprises eight QSC KLA12 elements (four per stereo channel) and two KLA181 subwoofers, all finished in white to match the building's aesthetics.

The irregularly-shaped, predominantly glass-fronted building presented Prime Connections Inc – QSC’s distributor in China – with some acoustic challenges: ‘The directivity of the system had to be carefully controlled in order to minimise unwanted reflections from the glass walls,’ explains a PCI spokesperson.

‘With its precise directionality and calculated vertical coverage, the QSC KLA system enabled us to keep the sound away from the glass walls, ensuring that the amplified sound in the hall remains clear with accurate imaging, and the spoken word is reinforced for live broadcasts without compromising intelligibility.’