CREATE TABLE "table1_25276250_3" (
  "driver_unit_model_no" text,
  "release_year" real,
  "output_voltage_rms" text,
  "inputs" text,
  "outputs" text,
  "notes" text
);

Question: What year were outputs is 2x pro bias, rca loop out and notes is vacuum tube released?
SQL: SELECT "release_year" FROM "table1_25276250_3" WHERE "outputs"='2x Pro Bias, RCA Loop Out' AND "notes"='Vacuum tube';

Question: How many outputs are there for solid state, battery operated for portable use listed in notes?
SQL: SELECT COUNT("outputs") FROM "table1_25276250_3" WHERE "notes"='Solid state, battery operated for portable use';