text: These instruments play the first two statements of the opening canon theme in Henryk Gorecki's Symphony of Sorrowful Songs.
full_question: These instruments play the first two statements of the opening canon theme in Henryk Gorecki's Symphony of Sorrowful Songs. At the beginning of the third movement of Mahler's first symphony, a muted one of these instruments plays a minor-key version of "Frere Jacques" above the timpani. A "C- extension" is often added to this instruments to extend their range downward. Schubert's Trout Quintet (*) replaces the second violin with one of these. Unlike the rest of the strings, this instrument does not use fine tuners and its strings are tuned in fourths. Prior to the 19th century, it usually doubled the cellos an octave lower in orchestral music. For 10 points, name this lowest-pitched member of the string section.
first_sentence: These instruments play the first two statements of the opening canon theme in Henryk Gorecki's Symphony of Sorrowful Songs.
raw_answer: double bass [or string bass or contrabass]