Jack was born in London on 11 July 1921. His musical career started when discovered singing by his father and mentor, the late Harris Philip Rosenberg, who was himself a composer of note and choirmaster at the New Synagogue, Egerton Road, Stamford Hill, the flagship of the United Synagogue at that time.
In his father’s choir, Jack’s beautiful voice developed. He had a three octave range, which retained its melodious quality throughout his life. Self-taught, he was an accomplished pianist, organist, arranger and composer.
As Jack matured, he often took over as choirmaster, particularly when his father became ill in his latter years. Before he died in 1953, Jack promised his father that he would lead the choir for the High Holy Days. He found that conducting came naturally to him and the Egerton Road choir for men and boys flourished under his leadership until 1963, when Jack and his family moved to Finchley.
Jack’s intention was to join his new community as “just a member.” However, soon after his arrival, efforts were made to persuade him to lead a Finchley Synagogue choir. Jack relented and his association with the Shul was to last nearly 40 years. Jack’s talent for choral music enhanced the davening of the many Chazanim with whom he was associated over the years. He admired their talent and, in turn, they appreciated his guidance and support. As well as his leadership of the Kinloss choir, Jack was also instrumental in training the choir at Norris Lea. He considered it a privilege to give his talent and knowledge to the community, always doing so in an honorary capacity.
During his musical career, he conducted many Sephiras HaOmer and Selichot services, none more poignant than the last United Synagogue service at the New Synagogue, Egerton Road, when Chazan Chaim Adler came from Israel to sing at Selichot.
In later years, Jack became well known for his charitable activities. Working with a small and dedicated committee, he arranged annual Chazanut concerts, which attracted the greatest Chazanim in the world to London. These hugely popular events raised substantial sums for charity.
Many of today’s Chazanim and choirmasters recognise Jack as one of the greatest in his field of his generation. He was not only a very talented man himself but he had that rare ability to share his love of music, to teach and inspire others. He wrote many new compositions and arrangements, several of which have become traditional pieces sung in Shuls throughout the world. Jack always cherished the memory of walking into Shul in Jerusalem to be greeted with the melodies of his own compositions.
Jack met his beloved wife Hilda just as the War ended. They were married in 1946 and spent 58 happy years together. Hilda & Jack had three children, Jeffrey, Jodi and Harris. When Hilda suffered a stroke some years ago Jack happily accepted the role of carer, in which his kind and thoughtful nature shone through. Jack was a man of integrity, a larger than life character who was respected and held in great affection by everyone who knew him.
A successful entrepreneur in his business life, Jack built up a substantial clothing manufacturing company, which was a major employer in Shoreditch and East Ham. He was also active in Freemasonry and, well into his seventies, he became the proud Master of Mount Zion Lodge.
Three weeks before Jack died on 24 August 2004 (7 Ellul 5765) shortly after celebrating his second bar mitzvah at Finchley Synagogue, a large congregation was present to hear him sing his maftir and haphtorah with great aplomb and vigour. He had the pleasure of having his sons and grandson participating in the service with him and of hearing Rabbi Mirvis, the Rabbi of the congregation, refer to him as ‘Mister Music’. It was to be the last time his beautiful voice was heard in the Shul.