Show off your music theory chops with my weekly challenge! You’ll find a new question posted here every Monday, and you can comment to post your reply.
This week’s challenge:
Here’s the beginning of a fugue in A major. Is the answer real or tonal?
Check back on Friday, April 30 for the answer (literally)!
ANSWER for 4/26/21
This is a TONAL answer to our fugue subject.
A real answer is identical to the fugue subject, note for note, merely transposed to the key of V. But a tonal answer is slightly altered so that its first few notes sound like we’re still in the key of I. The DO–SO leap in the subject (A to E) is reversed to SO–DO in the answer. This makes the transition from subject to answer smoother and less jarring. Tonal answers typically follow fugue subjects that have this explicit leap (DO to SO, or vice versa).
Composers deemed this necessary because the fugue was a musical form that appeared before the rules of common-practice harmony had fully cemented. If you want to modulate from the tonic key to the dominant (I to V), the common-practice method is to use an applied dominant. In this case, you’d write a II7 chord (V of V) and tonicize the new key. But in a fugue, we don’t do this. We have the subject in the key of I, and then BAM––we have the answer in the key of V. So the tonal answer was a kind of workaround, smoothing over the key change.
I’m about to finish the next video in the Counterpoint Module! Sign up for a monthly subscription for full access to all video lessons, worksheets, and answer keys. Find out how to weave melodies together like magic threads, and stay tuned for future lessons on fugues.
I’ll take a guess and say real, because I see an extra sharp near the end that wasn’t in the original and it seems like it wouldn’t be there if it were tonal. Disclaimer: I have no idea if I’m actually right but it’ll be fun to find out!
Aron Bernstein says
Hey Alan, good guess! An answer is really just the subject transposed to the key of V. The sharp near the end is there to keep that part of the fugue answer the same as the subject. The penultimate note of this melody is the leading tone (7th note of the scale). For the subject in the key of I, that note is G sharp, but for the answer in the key of V, it’s D sharp. So, in terms of intervals, that part of the melody is unchanged. It’s the first few notes that have been altered to create a tonal answer.