In AP Music Theory, a canon is a polyphonic texture device in which a melody is stated by one voice and then imitated exactly by one or more other voices entering at fixed time intervals, with the imitation continuing throughout the passage (Topic 2.12, LO 2.12.A).
A canon is the strictest form of imitation. One voice (the leader) states a melody, and another voice (the follower) enters a set distance later and copies it note for note, often at the same pitch level or at a fixed interval like the octave or fifth. The key word is strict. In a canon, the follower keeps imitating the leader for the whole passage, not just for a few notes.
Think of it as a musical relay where everyone runs the exact same route, just starting at different times. A round like "Row, Row, Row Your Boat" is the most familiar example, since a round is simply a canon at the unison that loops back to the beginning. On the AP exam, canon lives in Topic 2.12 (Texture Devices) as one of the devices associated with polyphony, alongside imitation and countermelody. When you describe a texture, the type (polyphony) tells half the story and the device (canon) tells the rest.
Canon sits in Unit 2 (Music Fundamentals II) under Topic 2.12, supporting learning objective 2.12.A, which asks you to identify texture devices in both performed and notated music. The CED's essential knowledge specifically lists canon as a polyphonic texture device, grouped with imitation and countermelody. That grouping is your study map. Texture questions on the exam expect more than "this is polyphonic." They expect you to name the specific device creating that polyphony, and canon is one of the cleanest devices to spot because every voice carries the exact same melody. If you can hear or see one melody chasing itself through multiple voices, you can lock in the answer fast on aural and score-based multiple choice.
Keep studying AP Music Theory Unit 2
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view galleryImitation (Unit 2)
Imitation is the parent category and canon is its strictest child. In general imitation, a voice copies another voice's idea for a while and then goes its own way. In a canon, the copying never stops. If the follower breaks off and does its own thing, you're looking at imitation, not canon.
Counterpoint (Unit 2)
A canon is counterpoint with a built-in trick. The composer writes one melody, but it has to sound good against a delayed copy of itself. Every canon is automatically contrapuntal because two or more independent lines are sounding together, which is exactly what counterpoint means.
Fugue (Unit 2)
A fugue also opens with voices imitating a subject, but after the opening the voices gain freedom, adding episodes and countersubjects. A canon never lets go of the imitation. Knowing that difference helps you answer comparison questions about polyphonic forms.
Ostinato (Unit 2)
Both involve repetition, but in different directions. An ostinato repeats the same idea over and over in one voice, while a canon passes the same idea across voices. Pachelbel's Canon famously combines both, with a ground-bass ostinato underneath a three-voice canon.
Canon shows up in Topic 2.12 texture-identification questions, both aural (you hear a passage and pick the device) and notated (you see a score and label the texture). The move you need to make is the same either way. First decide the texture type (a canon is polyphonic), then name the device by checking whether the voices share the same melody at staggered entrances. Practice questions in this area also test the related vocabulary, asking what a round is, which famous piece is a round, and what defines a fugue, so be ready to sort canon, round, fugue, and free imitation from each other. A common distractor pairs canon with countermelody. Remember that a countermelody is a different tune played against the main melody, while a canon is the same tune delayed in time. No released FRQ has used the word canon verbatim, but texture vocabulary is fair game anywhere the exam asks you to describe how voices relate.
Both start with voices entering one at a time on the same melodic idea, so they sound similar at the opening. The difference is what happens next. In a canon, every voice keeps imitating the leader exactly for the entire passage. In a fugue, the strict imitation only governs the opening (the exposition); after that, voices break free into episodes, countersubjects, and independent material. Quick test on the exam: if the imitation never stops, it's a canon. If the texture loosens up after the entrances, it's a fugue.
A canon is a polyphonic texture device where a follower voice imitates the leader voice exactly, entering at a fixed time interval and continuing the imitation throughout.
The CED groups canon with imitation and countermelody as devices associated with polyphony under Topic 2.12 and learning objective 2.12.A.
A round, like "Row, Row, Row Your Boat," is a canon at the unison that can loop back to its beginning indefinitely.
Canon differs from general imitation because the copying is strict and continuous, not just a brief echo of an opening idea.
Canon differs from a fugue because a fugue only uses strict imitation at the start, while a canon sustains it for the whole passage.
On texture questions, identify the type first (polyphony) and then the device (canon), since both labels together fully describe the passage.
A canon is a texture device in which one voice states a melody and other voices imitate it exactly, entering at fixed time intervals. It's listed in Topic 2.12 of the CED as a device associated with polyphonic texture.
Yes, a round is a type of canon. Specifically, it's a canon at the unison where the melody loops back to the start, so the voices can keep cycling forever. "Row, Row, Row Your Boat" is the classic example cited in practice questions.
A canon keeps strict imitation going for the entire passage, with every voice singing the same melody at staggered entrances. A fugue only uses imitative entrances in its exposition, then lets the voices develop freely with episodes and countersubjects.
Not exactly. Canon is the strictest form of imitation. Generic imitation means one voice briefly copies another's idea, while a canon means the copying is exact and continuous from start to finish.
Listen or look for the same melody entering in different voices at staggered times, with the later voices matching the first one exactly. If the voices play different melodies against each other instead, you're hearing a countermelody, not a canon.