John Martin, 48, a Norwegian double bass player, was convicted of killing 38-year-old Russian-born pianist Strelchenko at their home in Manchester, northwest England, on August 30 last year.
Martin had denied the murder or manslaughter of his wife, who used the stage name Strelle, but accepted he "must be the man behind it".
He was cleared of the attempted murder of a male youth, who cannot be named for legal reasons.
Martin will be sentenced at Manchester Crown Court on Monday.
A friend who was staying with the couple at the time said Martin flew at Strelchenko "like an animal", throwing them both down the stairs before repeatedly punching his wife, saying "I want to kill her".
Martin said he had no recollection of the killing, having drunk cider on the night and mistakenly taken diazepam for around six weeks in place of his anti-depression medication.
When police arrived, Martin repeatedly said: "kill me, kill me please, I have nothing to live for, I do not deserve to live".
Strelchenko died in hospital. She had 76 injuries including 45 marks on her head and neck.
Her jawbone was snapped in half. Parts of her skull were severely fractured.
Strelchenko studied at the prestigious St Petersburg State Conservatory and made her debut aged 12 with the Leningrad Symphony Orchestra.
She had performed at New York's Carnegie Hall.
"She was extremely talented with much life ahead of her," the pianist's family said in a statement.
"We cannot express how devastated we are that her life has been stolen from her. We can try to repair our heartache although no matter how long the sentence is, it will not bring Natalia back or make our loss any easier."