It started with an advert in the Ham&High seeking the original members of a choir who sang on a legendary recording session.

Decca Records was searching for the boys from Highgate School who appeared on the legendary recording of Benjamin Britten's War Requiem in 1963.

They had just released a newly restored and remastered version of the double Grammy award-winning album - 60 years after the great British composer conducted it at the now demolished Kingsway Hall in Holborn.

The choir at Highgate School sang on the 1963 recording at Kingsway Hall in HolbornThe choir at Highgate School sang on the 1963 recording at Kingsway Hall in Holborn (Image: Courtesy of Decca Records)

The request 'if you were one of the choristers who performed at the original Decca Recording session in 1963 we want to hear from you,' was aimed at gathering as many surviving choir members to hear the newly remastered version.

It yielded a reunion of 15 former schoolboys last Thursday in Soho.

All share memories of being conducted by the master composer and helping to create what has become a defining recording in classical music, described by Gramophone magazine as "among the most magnetic performances of British music ever put on record".

Benjamin Britten himself conducted the soloists, choirs and orchestras for the recordingBenjamin Britten himself conducted the soloists, choirs and orchestras for the recording (Image: Decca Records)

All now in their 70s, they told the BBC of how the recording was a "gruelling" experience, with Russian soprano Galina Vishnevskaya screaming and throwing a fit.

They did not realise, but this because she was placed on a balcony next to adolescent boys while the male soloists Peter Pears, Dietrich Fischer-Dieskau, were downstairs next to the composer - Britten saw the soprano and choirn as representing heaven and so being higher, although she felt she was being discriminated against.

The anti-war classic, which sets the Latin Requiem Mass and verses from Wilfred Owen's war poems to music, was written to mark the consecration of the new Coventry Cathedral in 1962.

The 1963 recording by The Bach Choir, London Symphony Chorus, Highgate School Choir, Melos Ensemble, and London Symphony Orchestra is considered definitive.

Also captured on the fragile tape reels were secret recordings of Benjamin Britten's rehearsals.

He can be heard addressing the musicians and choristers: “Boys I know it’s first thing in the morning but please don’t make it sound like it is”.

"Don't make it sound nice. It's horrid, it's modern music."

The advert was inspired after surviving members of the original 1963 recording team, and composer John Rutter, who sang in the choir as a teenager, visited Decca’s London offices for a playback of the new remastering.

Rutter called it "a marvellous achievement," and Decca recording crew Michael Mailes and Peter Van Biene, now in their 80s, were both moved to tears by hearing the Dolby Atmos mix from the original mastertapes.

“It sounds like it was recorded yesterday,” they remarked.

It led to the reunion where the boys also told the BBC they remembered "the emotions, the excitement and the fun" of recording with Britten.