CREATE TABLE table_73777 ("Driver Unit Model No." CLOB, "Release Year" FLOAT, "Output Voltage  ( RMS ) " CLOB, "Inputs" CLOB, "Outputs" CLOB, "Notes" CLOB)

What year were outputs is 2x pro bias, rca loop out and notes is vacuum tube released?
SELECT "Release Year" FROM table_73777 WHERE "Outputs" = '2x Pro Bias, RCA Loop Out' AND "Notes" = 'Vacuum tube'
SELECT "Release Year" FROM "table_73777" WHERE "Notes" = 'Vacuum tube' AND "Outputs" = '2x Pro Bias, RCA Loop Out'