Feature
 
 
May 2001
 


Yuen
Long Theatre

Popular culture

Until recently, nearly all cultural facilities in Hong Kong can be grouped into one of three categories: the town hall, the civic centre, and the cultural centre. 
        Modelled on London's
Royal Festival Hall, the 35-year old City Hall was for a long time the only major venue for a variety of cultural performances. Shatin and Tsuen Wan town halls were built in the same mode. Community events were catered for by small civic centres in districts such as Sheung Wan, Ngau Chi Wan and Sai Wan Ho; which were often grouped with other community facilities such as libraries and markets. 
        Then there is the Cultural Centre, a major performance arts complex with dedicated facilities for different types of performances. The Concert Hall, Grand Theatre and Studio Theatre are also complemented by a large lobby where exhibitions can be held.

The concept of smaller arts venues in off- centre locations resulted in the development of Ko Shan Theatre. Built in 1984, Ko Shan Theatre was a semi-open venue with an amphitheatre. It was extensively renovated and the public areas rebuilt in 1996. It was many years later, however, that the idea of having more small venues in places closer to the population centres in Hong Kong was given thought. In the 1990s, the former Regional Council decided to proceed with the development of two dedicated venues, one for theatrical and the other musical performances. 
        Although it was meant to be suitable for a variety of purposes, Yuen Long Theatre was essentially designed for musical performances just as Kwai Tsing Theatre (see BJ March 2000) was essentially designed for theatrical performances. 
        This fundamental difference is evident in the shape of the auditorium at Yuen Long Theatre as well as its acoustics design. While Kwai Tsing is wider than it is long, to provide more space for action and viewing, Yuen Long is just the opposite. It is longer than it is wide, in the conventional double cube or shoebox layout of musical performance venues designed to enhance the quality of the music. 
        In fact, the Architectural Services Department had a very specific brief with regard to the purpose of the auditorium: while it should be suitable for many types of performances, it must be principally designed for orchestral concerts. Consequently the auditorium was designed with a large acoustic volume in mind, "to create a natural orchestral sound" according to the architect. 
        Yuen Long Theatre has a Midas XL-200 40-input sound system with two main output, eight independent group output and four auxiliary output. Unlike Kwai Tsing, it does not have acoustic towels or a separate ceiling. What it uses to adjust the acoustic volume are 24 remotely-controlled, motorised drapes which can be extended to cover the side walls and roof slab. According to Mark Taylor, Technical Director of the Leisure & Cultural Services Department, the 12 sets of vertical drapes covering the side walls are normally open for musical events, but can be closed to provide more acoustic absorption during non-musical events. Depending on the demands of a conductor or orchestra, they can also be adjusted to provide the right amount of reverberation during an orchestral performance. 
        Six large, black horizontal drapes covering the ceiling slab can also be moved at the press of a button, to cover the reflective material in the ceiling and deliver the acoustics required. Stopping points between the drapes' open and closed limits allow for fine adjustments. 
        Acoustic panels hung on four motorised bars suspended from a grid above the forestage are another device for adjusting the acoustic volume. When a musical acoustic is not required, the panels can be hung vertically from two bars while the other two are used for suspending stage lighting or loudspeakers. 
        Mr Taylor said the acoustician provided some guidelines for moving the drapes and panels to suit the acoustic demands of different performances, as a starting point, but the theatre's
technical department would then have to build up a database as the theatre is used for actual performances in the years to come. 
        "The best way is for a good stage manager who knows how the elements work and what to do with them to write it out," he observed.
        Getting the acoustics right for any kind of performance is a fine art. The size of the auditorium, the optimum distance between the orchestra and the audience and the choice of fittings all have to be carefully worked out. 
        The timber used in the theatre, for example, must be of the right density. 
        "Timber is usually specified in terms of density, which affects the reflectivity. Dense hardwoods are preferred to maintain the 'live' feeling within the hall by reflecting virtually the full spectrum of sound frequency. It is also important to ensure timber is a minimum of 25 mm thick, preferably 38 mm, to avoid excessive loss of bass response," Mr Taylor explained. 
        Even the type of upholstery used for the seating must be carefully chosen. 
        "Apart from comfort and fire safety issues, a seat requires materials that roughly approximate the absorption effect of a human body so that even if it is empty, it doesn't
make the venue sound different." 
        Air-conditioning is always an issue in a theatre because of the noise air-conditioning systems make. To maintain a noise level of 26 dB, the air velocity must be kept low. Rather than pushing fresh air through narrow ducts, therefore, large ducts are installed to allow a large volume of air to virtually drop into the auditorium. In addition baffles and silencers were put in to act as mitigators. 
        Yuen Long Theatre has 923 seats in two tiers: 650 in the stalls and 189 in the balcony, plus an additional 84 on the orchestra pit elevator when it is not needed for the performance. The adjustable proscenium is 11-15 m wide and 7-9 m high. Its width is adjusted by moveable towers which, when not needed, can be hoisted away and stored in the fly tower. The distance from the proscenium to the back of the stall and from the proscenium to the back of the balcony are both 25.5 m. The stage is 29.5 m wide, 23 m high and 31 m deep, including the side and rear. The left side and rear stages are separated by vertical shutters which allow scenery to be moved around in these areas without the main stage being disturbed. 
        A stage wagon with a 11 m diameter revolving platform can be used to move scenery between the rear stage and main stage area. Compensating elevators are used to lower it until it is flush with the floor, and removable floor modules on the platform and the main stage elevator allow traps to be installed as needed. 
        The orchestral shell is a moveable one which can be transported using air castors with tuggers to a dedicated store within the backstage. A film screen on the back of the shell enables the theatre to be used for screening 16/35 mm films. Unlike Kwai Tsing Theatre, which employs a computer-controlled suspension system only, Yuen Long Theatre has the option to use manual counterweight bars as well as a computerised suspension system. 
        Underneath the orchestra pit are two lift units which are used to adjust the size of the forestage. The inner lift adds 30 sq m to the forestage while the outer lift adds 42 sq m. When both are raised, therefore, an additional 72 sq m of space will be created to accommodate up to 86 musicians on stage. The additional seats to be installed on the orchestra pit are normally stored under the auditorium. These are mounted on wagons with air castors, to facilitate their move in and out of storage.
        In addition to the auditorium, Yuen Long Theatre also contains a dance studio, a rehearsal room, a lecture room and a restaurant. Both the dance studio and the rehearsal room are sound-proofed and fitted with sprung floors. 
        All these facilities are packed into a 14,800 sq m complex expressed as a series of cubical forms designed to reflect the functional spaces inside. The facade is clad in pink and grey ceramic tiles similar to the predominant colour scheme of the area. The west-facing front elevation is clad in laminated tinted glass to cut UV transmission and reduce heat gain. 
        In response to the client's
request for a main foyer where small performances and exhibitions can also be staged, a spacious, 11 m high foyer was created with a full-length curtain wall providing views of a courtyard, blurring the difference between indoors and outdoors. 
        Yuen Long Theatre was constructed at a cost of HK$390 million. Open since mid-2000, it has already played host to a variety of performances, from ballet to symphonic concert, Cantonese opera to chamber music, fulfilling its purpose of bringing culture to the masses.

client Leisure & Cultural Services Department
architect Architectural Services Department
main contractor Woon Lee Construction


-- Building Journal