Handel. 'Messiah.'
Here the first five notes only of the subject are taken for the stretto, the continuation of the passage being new. The stretto is at one crotchet's distance in all the voices, and is in reality a canon 4 in 1, at the octave and fourth below.
274. A fugue subject may also in a stretto be taken by inversion, augmentation, or diminution, or any combination of these, instead of in its original form. No rules can be given as to when these devices should be employed; this must be left to the judgment of the composer. We give a few examples. The subject of the 6th fugue in the 'Wohltemperirtes Clavier' is the following—
J. S. Bach. Wohltemperirtes Clavier, Fugue 6.
The answer enters in the third bar. In the course of the fugue we meet with the subject slightly altered in form (a major third being substituted for a minor), and imitated at one bar's distance by its own inversion.
Later still all three voices of the fugue take part in the stretto, the inverted subject now leading.