Although the audience figures are not made public, internal figures held by the orchestras indicate that both the Royal Festival Hall and the Barbican are playing to 50 per cent to 55 per cent full houses for symphonic concerts.
These figures, low as they are, include many tickets that are given away to the media or distributed discreetly within the music industry and beyond. In one case, a kitchen porter at a London teaching hospital has been responsible for handing out free concert tickets to nurses and medical students over a number of years.
A senior orchestral source told the Independent yesterday that the practice of giving concert tickets away, or "papering", is widespread within the classical music industry. "Promoters, concerned that concert halls will be empty, use a clandestine network of contacts to put the word out that the tickets are available," she said.
"Hospitals and fire stations are often used. One contact at a London hospital, who is used regularly, can produce 200 to 300 people on one night."
Some free seats are disguised in audience figures and accounts by charging a nominal fee, thus allowing the orchestras to count the free seats as paid for.
According to one former orchestra administrator, it is not uncommon for pounds 45 tickets to be sold for 50 pence. "The ludicrous situation often arises when people sitting in adjacent seats have paid a few pence and over pounds 40 respectively."
Richard York, deputy chief executive at the City of Birmingham Symphony Orchestra, has wide experience of leading London venues. He said yesterday: "Papering the house with giveaway tickets is a common practice in the capital. It takes place on a fairly regular basis to fill houses that would otherwise be an embarrassment."
The Barbican Centre admitted yesterday that it is one of the venues where papering takes place. Lisa Collins, a press officer, confirmed that the practice occurs, but would not "divulge commercially sensitive information on pricing and promotions".
A spokesman for the Royal Festival Hall, which attracts average audiences of 1,700 per performance against its 2,700-seat capacity, denied that "papering" was officially sanctioned, but refused to give box-office revenue figures.
Part of the reason for declining audiences is that young music lovers, raised on three-minute pop discs and quick-cut television soaps, lack the patience to sit through an hour of Bruckner. Senior citizens, who form the bulk of subscribers, often now fear to venture into inner cities. The practice of massaging audience figures is detailed in a new book on the classical music industry to be published next month.
8 When the Music Stops; Norman Lebrecht; Published by Simon & Schuster on 1 July; pounds l6.99.