CREATE TABLE table_66732 ("# Tubes" CLOB, "Converter" CLOB, "Det/Pre-amp" CLOB, "Audio Amp" CLOB, "Rectifier" CLOB)

Name the # tubes with audio amp of x
SELECT "# Tubes" FROM table_66732 WHERE "Audio Amp" = 'x'
SELECT "# Tubes" FROM "table_66732" WHERE "Audio Amp" = 'x'