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165 Crystal Vision interface boards have been used by BBC Studios, part of BBC Resources Ltd., a wholly owned commercial subsidiary of the BBC, for the HD upgrade of its Studio Four at BBC Television Centre in London.

BBC Studios is investing nearly two million pounds in HD cameras, lenses, vision and monitoring equipment to support its entertainment production customers. Studio Four comprises 8,000 square feet and is home to “A Question of Sport”, “The Jonathan Ross Show” and ITV1’s “The Alan Titchmarsh Show”. The new Studio Four is designed to work in any of the current HD and SD formats, can produce HD and SD simultaneously and includes Dolby E encoding.

The up and down conversion is provided by 20 of Crystal Vision’s Up-and-down up/down/cross converters and 13 of the Q-Down123 short-delay down converters. The Up-and-downs will be used to convert existing legacy SD equipment to HD, with ten of them wrapped around the main matrix to provide additional feeds as required. The Q-Downs will provide the SD feeds when the studio is in HD mode. Explained Danny Popkin, Technical Development Manager for BBC Studios: “Much of our output will be simulcast in SD and HD, so the short delay of the Q-Down is ideal for this use.”

Distribution of the HD signals will come from 17 of the HDDA105N and HDDA111N distribution amplifiers. Three SYN HD synchronisers will be used for synchronising internal sources that either do not have locking feeds or are unstable. BBC Studios will also use five of the new SYNNER-E HD multi-functional synchronisers – which include an embedder, de-embedder, tracking audio delay, audio processor and special Dolby E processing – for synchronising external sources to the studio and de-embedding the audio to AES. Two CoCo HD colour correctors and legalisers will be used to feed in-vision monitors or colour correct incoming pictures.

For the audio, BBC Studios will use 26 of the TANDEM HD-21 embedders/de-embedders. Explained Popkin: “To simplify VTR plugging, all the studio recording is done as embedded AES so there is an embedder/de-embedder either side of any recording device”.

The studio matrix is either SD or HD, and PAL or Y/C sources and displays will therefore use the ADDEC-210, ALLDAC and MON210 converters to encode or decode PAL. Other Standard Definition boards used in the installation include VDA110R and DDA108 distribution amplifiers, SYN102 and SYNNER-E synchronisers and the TANDEM-200 audio embedder/de-embedder.

The boards are mainly housed in Indigo 4SE 4U frames – selected because they offer the highest density of boards (holding up to 24) with BBC Studios having limited space for rack equipment. Control comes from the Statesman PC software, with BBC Studios using the Signal Path add-on – which provides a view of the system based on the way the boards are used rather than their rack location – to graphically monitor its signal paths, because it simplifies fault finding in a complex signal chain.

The equipment was ordered and installed by Dega Broadcast Systems, with the studio going on air in early September.

Studio Four is the third studio that BBC Studios has upgraded to HD. Explained Popkin: “There is an increasing demand for HD content and this investment will ensure BBC Studios continues to fulfil the requirements of its customers, whose creative and editorial visions are increasingly in HD. It will also help the BBC achieve its HD aspirations.” Crystal Vision was also selected for the HD upgrade of Studio One in 2006, which included 72 of the Up-and-down up/down/cross converters.

Based at Whittlesford near Cambridge in the UK, Crystal Vision provides digital keyers, picture storage modules and a full range of interface equipment including converters, decoders, encoders, distribution amplifiers and audio embedders to the professional broadcasting industry worldwide.