Boris Christoff had an excellent voice with a distinctive dark tone. Although it was not as large as some other bass voices, he had no trouble making an impact in big spaces like the San Francisco Opera. Owing to his stage presence and dramatic temperament, he was a worthy heir to the grand tradition of Slavonic basses exemplified by
Fyodor Stravinsky,
Lev Sibiriakov,
Vladimir Kastorsky,
Feodor Chaliapin,
Alexander Kipnis and
Mark Reizen, among others. Christoff made studio recordings of eight operas (
Don Carlo,
Boris Godunov and
Faust twice each) In 1963 he was invited for the second time to record
Boris Godunov in Paris, again performing all three bass roles. Нe suggested that the choir of the
Sofia Opera be invited as well. An EMI representative was sent for an audition in Sofia, who was convinced of Boris Hristov's judgement, and so the choir took part in the recording conducted by
André Cluytens, called triumphal. While he was a grand performer on stage, Christoff had difficult off-stage relations with some fellow singers and producers, which sometimes grew into public scandals. In 1955 he fell out with
Maria Callas during the performances of
Medea at the Rome Opera. In 1961 his contract with
La Scala was terminated after an open conflict with fellow Bulgarian
Nicolai Ghiaurov. In fact, Boris Christoff opened the way for the Bulgarian singers Nikolay Ghiaurov and Dimitar Uzunov to La Scala—it is entirely his merit to attract them as his partners in
Boris Godunov. The ambitious Ghiaurov, whose brother Kostadin Ghiaurov was a senior functionary of the
Bulgarian Communist Party, began to speak out against him and call him a "fascist", and Boris Christoff blamed him for collaborating with the Bulgarian communist regime. The communist regime's hatred for Christoff who was not even allowed to go to Bulgaria for his father's funeral pushed Ghiaurov further into rivalry with Christoff.
Herbert von Karajan tried to make Boris Christoff sing the title role in
Don Giovanni which would have been inappropriate for his range; this prompted him to sever relations with von Karajan. He was the brother-in-law of the Italian baritone
Tito Gobbi. in Sofia, Bulgaria ==Recordings==