“The strictest form of counterpoint.”
A subject enters alone in the first voice and is called the antecedent. The subject enters again in another voice and is called the consequent.
Although there are various methods that essentially alter the subject, i.e. enter at another interval other than the octave, or reversing the subject (retrograde) et al, I will stick to only the most basic methods. The simplest methods can be found in Quarenghi’s own composition.
There he composes with the subject, antecedent and consequent entering only at the octave during the main body of the canon. There are four entries there. But one interesting and technique he uses alters how we perceive the subject. With each successive entry the consequent gets more impatient, entering sooner. By the time we get to the fourth entry the two voices are separated by a mere quarter note!
To finish the canon, he effectively adds a CODA, and is quite clearly that since it has a conclusive feel to it. Here Quarenghi utilizes four advanced methods of alteration to the subject. Those are as follows, in pairs: the antecedent is augmented and a third above, the antecedent is diminished and enters at a fourth below.
Listen to my podcast episode about the musical Canon here: https://open.spotify.com/episode/21Nxx5dK6vR1hwSuIRQXy2?si=1_FHqy_3RFKi6n2g-qwXJQ