Semicadence


Any deviation from the formula of the perfect

cadence--either in the choice of some other than the tonic chord, or in

the omission of the keynote in either (or both) of the outer

parts--weakens the force of the interruption, and transforms the

cadence into a lighter, more transient, point of repose, for which the

term semicadence (or half-stop) is used. The semicadence indicates

plainly enough the end of its phrase, b
t does not completely sever it

from that which follows.



It is these lighter, transient forms of cadence to which a number of

different names are given; for the student of analysis (and the

composer, also, for that matter) the one general term semicadence, or

half-cadence, is sufficient, and we shall use no other.



If, then, a cadence is final in its effect, it is a perfect one; if

not, it is a semicadence. The harmony most commonly chosen as the

resting-place of a semicadence is the chord of the dominant,--the

fifth step of the momentary key,--that being the harmony next in

importance to that of the tonic (the one invariably used for the

perfect cadence). The following example illustrates the dominant

semicadence:--





The cadence-chord is the dominant harmony (root e) in the key of A

minor; neither of the two upper tones on the first and second beats is

the root of the chord; it is quite sufficient that the root appears as

lowermost tone, and even this is not necessary. The point of repose

is shifted to the second beat, in the manner so amply illustrated in

the examples of the disguised cadence; the methods we have seen may be

applied to any kind of cadence.



See also Ex. 18; the key, and therefore the chord, at the semicadence

is the same as that of the above example (simply major instead of

minor).



Also Ex. 23, No. 4; the semicadence chord is the dominant harmony of

E-flat major; it is skillfully disguised. Ex. 25, dominant harmony of

A major. Ex. 26, last four measures; the semicadence is made upon the

dominant of C minor.



In the following:



the semicadence in the fourth measure is made with the dominant harmony

of C major (the tones g-b-d-f); it is so disguised as to remove all

signs of interruption; but the chord prevails throughout the measure,

and (as may be seen by reference to the original, op. 68, No. 3) the

next measure--the fifth--exactly corresponds to the first; this

indicates another beginning, and proves our ending.



But though the dominant is thus generally employed at the semicadence,

it is by no means the only available chord. It must be remembered that

every cadence which does not fulfil the definite conditions of the

perfect cadence, is a semicadence. Examine each of the following, and

determine why the point of repose is each time a semicadence:--Ex. 1;

Ex. 9, No. 3; Ex. 14, No. 2, fourth measure; Ex. 14, No. 3, fourth

measure; Ex. 19; Ex. 22, Nos. 3 and 4; Ex. 23, No. 2, fourth measure.



The distinction between the two species of cadence becomes most subtle

when the tonic harmony is chosen for the semicadence, but with some

other part of the chord than the keynote as uppermost (or lowermost)

tone. This might appear to lighten the perfect cadence too

immaterially to exercise so radical an influence upon the value

(weight) of the interruption. The keynote, however, is so decisive

and final in its harmonic and melodic effect--everywhere in music--that

its absence more or less completely cancels the terminating quality of

the cadence-chord; in other words, the force of a tonic cadence depends

upon the weight and prominence of the keynote.





The first, second, and third of these cadences is made upon the tonic

harmony, on the accent of each successive fourth measure. But they are

only semicadences, as the melody (uppermost part) rests upon the

Third of the chord, c, instead of the keynote; this substitution of

c for a-flat is sufficient to frustrate the perfect cadence and

diminish it to a transient interruption. The final cadence is perfect,

however, because there the uppermost tone is the keynote. See also

Ex. 21; and Ex. 17, No. 2, fourth measure (semicadence, with a

instead of f as principal tone in upper part, and disguised by the

continuation of rhythmic movement to the end of the cadence-measure).

In Ex. 17, No. 1, the cadence is made with the tonic harmony of G

minor, but with the Third (b-flat) at the top.



More

;