What makes a building an Opera House? It must have a large stage with full facilities for the use of extensive scenery, and a pit large enough for a full-sized orchestra. The combination of fully-equipped stage and large pit is essential for classical ballet as well as opera performances, and most opera houses are now home to both opera and ballet companies¹.

However, many features of a traditional opera house have other origins. The importance of boxes, for example, arose from the historic position of the opera house as a social meeting place for the aristocracy.

The Stage and Backstage

Above the stage, the tall fly tower allows scenery to be completely raised, using a combination of counter-weights and pulleys. The combination of manpower and stage machinery allows a traditional opera house to produce a surprising range of special effects: one grand opera of the 1820s went so far as to have Vesuvius erupting on stage. The area behind the stage is usually a warren containing dressing-rooms, rehearsal rooms, storage rooms and workshops. The legendary feuds carried on here rarely affect the front of the house. The Stage Door, however, is often a magnet for fanatical opera-goers, who lie in wait for their favourite singers after every performance.

The Pit

This is the space for the orchestra, which nowadays may have over a hundred musicians. It sometimes extends quite a distance under the stage. If the work performed is in an exotic style, or by a modern composer, the array of instruments may be as interesting as what is happening on stage.

The Auditorium

In a traditional opera house, this is normally U-shaped, with the length of the sides deciding the audience capacity. The ground floor seats are usually called the Stalls. The arrangement of balconies can be:

• Tiers of boxes, with open galleries only at the highest levels. This is typical of the oldest and most aristocratic houses, such as La Scala (Milan) and Vienna.
• Large open galleries at mid-level, with boxes only along the narrow viewing areas at the side. This is found in many houses built from 1850 onwards, such as Covent Garden, London.
• Open galleries at all levels. This is the normal arrangement in opera houses designed in the 20th century.

The Stalls

Sometimes known as the Parterre, or Orchestra Stalls, these seats have the closest clear view of the stage. The larger the opera house, the more noticeable this advantage, so that they are usually among the most expensive seats. Depending on the acoustics of the building, the sound may be less well-balanced, especially for those sitting close to the brass section of the orchestra.

The Boxes

A box is a balcony section divided by partitions from the neighbouring boxes, with a separate door, furnished with moveable chairs and stools rather than fixed seating. Historically, subscribers often either owned the box or could reserve it for the full opera season. The number and arrangement of the boxes reflects the early importance of the 'high society' aspect of the opera house.

The Social Advantages of a Box at the Opera

• It is possible to sit down comfortably in a wide-skirted ballgown.
• Friends and hangers-on can easily visit you at the interval.
• You don't have to stand up to let lesser mortals pass.
• Everyone else can see when you arrive and who is with you.
• Judicious use of opera glasses will allow you to decide which of your acquaintances is wearing the most impressive jewellery, and to follow the progress of interesting flirtations.
• The relative privacy once the lights have gone down gives considerable opportunity for a variety of activities.

The Royal or Imperial Box

In an opera house with full tiers of boxes, such as the Vienna State Opera, it is possible to have a particularly ornate and important box at the middle of the lowest tier, providing the best sight lines to the stage. This usually became the Royal (or Imperial) Box, reserved for the ruling family and their friends.

It is typical of the more half-hearted approach in England to both opera and the Royal Family that the Royal Box in Covent Garden is at the side of the auditorium, with a skewed and inferior view of the stage. By sacrificing the best view, however, this Royal Box has the advantage of a private entrance and separate toilet facilities, which on balance is probably a better deal than the more ostentatious Imperial Boxes of the Tsars and Kaisers.

The Practical Disadvantages of Opera Boxes

• 
  The presence of boxes along the sides of the horseshoe makes little difference to the seating capacity, but the seats or stools at the back of these boxes have a particularly poor view of the stage.
• More importantly, full tiers of boxes waste the best viewing space, directly opposite the stage. This is the main reason they have fallen out of favour.
• Finally, the presence of full tiers of boxes makes cleaning and maintenance more expensive.

Mid-level Galleries

These galleries are variously known as the Grand Tier, Grand Circle, Circle or Upper Circle. While in a large house the seats may be far from the stage, the combination of good acoustics and good sightlines often makes them the ideal position. They have a far larger seating capacity than an equivalent tier of boxes. For this reason, modern opera houses usually have galleries, and no boxes at all.

High Galleries

These galleries may be called the Amphitheatre, 'The Gods', the Balcony, or in colloquial terms 'the nosebleeds'. Once the place for the footmen accompanying the denizens of the boxes, these galleries have an almost vertical view of the stage, and are rarely suitable for sufferers from vertigo. The social distinction between these galleries and the more expensive areas is often rubbed in by the management's insistence that people use a side entrance and plain stairway to reach them.

The main compensation for the more spartan conditions is that the audience here is generally more knowledgeable than that in the boxes. The applause of these galleries is often the best measure of the real quality of the performance.

Historically, the upper galleries were usually the home of the dreaded claque. This was an organised group of regular patrons who would applaud or boo to order, and who often managed to extort large sums from intimidated singers trying to ensure a good reception.

Renovations

In the 2nd half of the 20th Century, a number of new opera houses were built, including the Metropolitan Opera House at Lincoln Centre in New York, and the Opéra Bastille in Paris. The increased audience comfort, and shiny new machinery, encouraged the managements of many older opera houses to plan major renovations.

Backstage

The possibilities for backstage improvements are limited by the floorspace available for extensions, and the overall budget. A new stage may be built with 'wagons' or 'trains': large sections of floor which can be moved in and out of the stage area, carrying scenery with them. Giant acoustic barriers can allow rehearsals to be carried on in the adjoining area, while work goes on on stage. Sound-proofed rooms allow singers to go through the necessary warm-up exercises in comfort. Closed-circuit televisions give the singers a view of the conductor, no matter where they are positioned on the stage; if extended throughout the backstage regions, the television network can allow both the cast and stagehands to watch for their cues.

While lighting systems have got more and more complex, one thing that is not used in a traditional opera house is any large-scale sound system. Opera singers depend on their natural voices, without amplification, so any microphones to be seen are normally for radio or television broadcasts. No matter how much room is available on the site, both workshop and warehouse facilities are likely to be at a distance, with a fleet of lorries bringing scenery to and fro in an impressive display of logistics².

Public Areas

Artistically, the main modern improvement in the auditorium is the addition of screens for surtitles, so that the audience can now actually follow what is going on. Most opera houses have a surtitle screen above the stage. The deluxe system has a little individual screen for every seat: of course, in a fit of one-upmanship, most dedicated opera-goers will turn this off, showing that they don't need to depend on translations.

Since summer heat could make conditions unbearable, the traditional opera season went from September (or October) to May. The addition of efficient air conditioning allows the house to be used all year round. A revamped auditorium usually give more legroom, while, to probably half the audience, the crowning jewel of a renovation programme is likely to be the provision of enough ladies' loos.

Other Features

The Historic Fire and Other Disasters

In the past, the use of candles, oil lamps and gas lighting meant that fire was always a danger, and most older opera houses have been destroyed by fire at least once. La Fenice ('The Phoenix') in Venice is actually called that because it rose from the ashes of a previous building. Other opera houses , including La Scala, Vienna and Dresden were badly damaged by allied bombing in the Second World War. More recently, sub-standard wiring, electrical faults and dodgy contractors have become a problem, as in the fire which destroyed La Fenice (again) in 1996.

Salons and Foyers

The more grandiose opera houses often have impressive public rooms at the front of the house, providing space for people to mix at the intervals. The really ornate salons can be recognised by names such as 'Salon Doré', and can be worth a visit in themselves. Nowadays these salons may be used for chamber music concerts.

The Chandelier

The ornate decoration of a traditional opera house is usually completed by the presence of a glittering giant chandelier suspended over the middle of the auditorium. The chandelier of the Palais Garnier in Paris is said to weigh eight tonnes. Young children and bored members of the audience may spend long periods of time calculating what damage would ensue if the chandelier just happened to fall down³.

The Bar

Bars and lobby areas can range from plush and luxurious in the stalls and main tiers, to spartan in the top galleries. Reluctant opera-goers may find that a drink in the Bar at the interval is the one thing that makes their evening bearable.