When cellist Mstislav Rostropovich made his British debut at the Royal Festival Hall and his American debut at Carnegie Hall in 1956, he was universally hailed as an exceptional musician. He had the mysterious charisma of a star, and backed it up with phenomenal talent, technique, passion for the music, communicative ability, and instinct for the composer's message. One of the remarkable qualities of his art was his unprecedented ability to project the instrument's sound with fullness and strength in all its registers. He had a full command of the multitude of special effects which are available on the instrument, and a wide variety of tonal color at his disposal. Also, his performances had a firm sense of rhythm, and a sure grasp of the structure and emotional logic of the composition.