He studied voice with R. Bērziņš in Riga.
During 1946-74, Frinberg was a soloist with the Latvian Opera.
From 1975, he was in charge of the operatic class at the Latvian conservatory.
His repertory included:
Pedro, Herodes, Otello,
Tannhäuser, Canio, Kutierma, Grigori, Radames, German, Vižuts (Baņuta by Kalniņš],
Aivars (Uz jauno krastu by Zariņš), Pyer, Sergey (Katerina
Izmailova), Lachplyesis (Ogon i Noch by Medins), ...
He toured in Finland, Canada, Czechoslovakia, Bulgaria, and Poland.