Here’s a choir that need never worry about attracting younger members. It runs its own school, with around 300 children, and from the age of ten the most musically gifted boys are channelled into the choir. The present membership of around 100 are in good company, as the 500-year history of the choir in its various guises is littered with illustrious names, either as choristers or directors: Mozart, Bruckner, Schubert, Haydn. Historically, the boys sang at the imperial court, then after the Habsburg Empire collapsed the choir became a private enterprise. Extra funding was needed for the boys’ upkeep and this is where concerts outside the Chapel Imperial came in, leading to a tradition of touring. In Vienna the boys sing as a whole group at Sunday Mass and sometimes at the Vienna Philharmonic Orchestra’s famous New Year concert at the Musikverein, but for their travels they are divided into four touring choirs.

Our particular entertainers, who were about to embark on a nine-week tour of the USA, were the Haydn Choir, and they opened the concert with a confident and convincing attack on their namesake’s punchy Insanae et vanae curae. It was a cleverly constructed programme showcasing half a millennium of repertoire relevant to Vienna, divided into sections covering “Music from the Chapel Imperial”, “Romantic Vienna”, “Wienerlied” and “Contemporary Vienna”, and despite their deep roots in history it showed they’re keen to deliver a more modern slant to their audiences. They took this just one step too far, I felt, with their second encore, a rendition of Queen’s Bohemian Rhapsody, complete with electric bass guitar and soloist’s microphone. Amplification and the Vienna Boys’ Choir just don’t seem to go!

On the other hand, incorporating material from Billy Joel was inspired, and it gave the boys the chance to show off their excellent English pronunciation skills alongside their undoubted prowess as musicians. Vienna brought the first half to a close, such that the audience traipsed off to the bar with the words “Vienna waits for you” ringing in their ears. The choir returned for part two intoning the introduction to Joel’s The Longest Time as they took their places on stage, simply grouped either side of the piano. This Night was an intriguing combination of music from Beethoven’s Pathétique Sonata and Joel’s words, which though technically well-sung seemed far too old in subject matter for this youthful choir, the oldest of whom was 14.

I can only begin to imagine what this peripatetic lifestyle is like at such a young age, but the choristers showed no sign of homesickness or stage fright, many of them even rising to the challenge of solos or duets. They were in good hands with their conductor Kerem Sezen, although for Mozart’s Più non si trovano he was ousted from his position of leading either from the front or from the piano, as one of the boys moonlighted as pianist and another gave his peers the beat, while Sezen sang bass with the choir. Their qualities as singers are many, particularly highlighted in Balduin Sulzer’s Laudate Dominum. Opening with carefully judged staccato phrases leading into a fascinating fugue, it gathered pace and brought to mind an unstoppable train, except that the singers were fully in control, with disciplined breathing and a strong sense of listening to each other.

To the audience’s delight, there were high jinks during one of the “Wienerlieder” – sadly unspecified, as according to the programme it should have been announced from the stage but no such announcement was made – when the boys put their love of acting, dancing and gymnastics into practice and the stage momentarily resembled a circus. Although stationary again, they also had a jolly good metaphorical romp through a couple of numbers by Johann Strauss II, arranged by Gerald Wirth: Morgenblätter Waltz (“Morning Paper Waltz”) and Tritsch Tratsch Polka, their tongues dancing round the fast and furious lyrics with boundless energy and plenty of forward momentum. This was met with delighted applause, concluding the official programme... but the boys had something extra up the sleeves of their sailor suits.

Reinhard Fendrich’s I am from Austria made for a totally appropriate encore. It was contemporary, upbeat and sung with feeling, and the boys clearly enjoyed the feel-good harmonies of this unofficial national anthem. This would have been the perfect point to bid us “auf wiedersehen”.