HAVE you ever wondered why the stillness of the studio from which a TV announcer talks is not broken by rumbles as the gang in the studio next door moves scenery, or as a pop group shouts away? Solid walls, floors and ceilings with acoustic treatment are part of the answer, but there has to be access through doors.
To reduce sound, the doors have to be special ones, and at the new Birmingham ATV centre there are nearly 100 designed, made and installed by Geo. W. King Ltd., a TI company, of Stevenage.
The doors are made of steel or wood and look like ordinary doors, but they have a special internal construction and this, with the seals around the edges, provides the all-important sound reduction.
Many have glazed ports so people can see what is happening on the other side, and others are also required to have fire resistance for specific periods.
The biggest doors are hinged pairs, 15ft. 4in. high and 14ft. 3in. wide, each leaf weighing 2½ tons. These have to be hung on massive hinges, and designed to close tightly on to sponge rubber seals.
Wedge-shaped clamps operated from a central control wheel through push-pull cables hold the doors firmly against their seals, to leave no gap that sound can get through.
Other doors have a sliding action, but all have to meet a specified sound reduction of 45 or 35db, to satisfy the stringent requirements of the architects, R. Seifert and Partners, their acoustic consultant, C. C. Buckle, with King’s acoustic consultants, Acoustic Designers, Ltd.
Geo. W. King also supplied and fixed doors to the changing rooms, reception and recreation areas; these were of the sliding and folding, and straight sliding types.