This is my maternal grandfather, Mordukh Yasnogorodsky. He was born in 1862 in Yasnogorodsk. Then he moved to Kiev.
His father, Nohum Yasnogorodsky, was a well known songwriter, and his cousin Meer Bernshtein was a famous opera singer who changed his name to Mikhail Medvedev. Mordukh also was musical and sang well.
Thanks to Medvedev's invitation to work in Saratov, the entire Yasnogorodsky family moved to Saratov, where Medvedev was professor of voice at the Saratov Conservatory.
By that time Mordukh had already married Nehama Dovgalevskaya. Mordukh took part in performances and occasionally sang in the choir of the Saratov Operatic Theatre.
He also worked there as an accountant. Mordukh died in 1942 in the city of Yalutrovsk (Siberia) where he had been evacuated during the blockade of Leningrad, at the age of 80. Unfortunately, I do not know any further details of his life, because he died when I was very young.