Polymetric
Polymetric is the technical term in music for the simultaneous occurrence of different meters in the different voices of a piece of music.
Polymetrics in Classical Music
In classical music it happens that polymetrics go hand in hand with an adaptation of the tempos of the different voices so that the overlapping bars of different time signatures have the same length, which means that note values in the voices have different durations. There are numerous examples of this in which different meters are superimposed in different time signature, but the meters sometimes coincide, for example:
- the aria My dear Savior, let me ask you in Bach's St. John Passion : Soloist and accompaniment are in 12/8 time, while the choir is in 4/4 time; This leads to polymetric shifts due to the adjustment of the duration of the bars as soon as the choir has its own eighth notes, which are one third longer than the eighth notes of the soloist;
- the ball scene in the first finale of Mozart's opera Don Giovanni : it features three different dances in different time signature (minuet, contratance and German dance).
Polymetrics can usually be recognized by the different accents in the individual voices, by the bar notation across the bar lines or (easiest) by the preliminary signing of different time signatures.
In non-European, especially African music , however, the polyrhythmics , which is sometimes confused with polymetrics, is not uncommon.
Polymetric in Modern Music
Polymetrics (without adjusting the duration of the bars of different time signatures) is also used extremely frequently in various subgenres of progressive rock and progressive metal . Prominent examples include bands such as Gentle Giant , King Crimson , Spastic Ink , Spiral Architect and Meshuggah . Here is a breakdown of two examples from King Crimson and an example from an album by two former King Crimson members:
- The song Thela Hun Ginjeet (e.g. to be found on the album Discipline ) has a superimposition of the basic structure in 4 ⁄ 4 time with a riff played by Robert Fripp in 7 ⁄ 8 time . With melodically and rhythmically consistent riffs, this creates different harmonic overlays in each repetition. Only after 56 eighth notes do the overlaid time signatures come together again.
- The former King Crimson drummer Bill Bruford explained at the beginning of the song Etude Revisited on with bassist Tony Levin rehearsed album Bruford Levin Upper Extremities the polymetrical overlay used in this song by 5 / 8 - and 7 / 8 -Takten.
- The song Frame by Frame from the album Discipline provides an example of a special kind of polymetric used by the band King Crimson. In time index 1:07 the two guitars start a unison -Riff in 7 / 8 -Stroke to play with changing accents. In the fourth repetition Robert Fripp can then at the reef an eighth note away and from there passes alternately the original Reef in 7 / 8 ¯ clock and the reef with an eighth less in the 6 / 8 ¯ clock. This results in an overlay of the basic riff in the 7 ⁄ 8 in the first guitar track with a change from 6 ⁄ 8 and 7 ⁄ 8 time in the second guitar track. The drummer plays a 13 ⁄ 8 riff over this, which, by shifting the accent, underlines both the basic 7 ⁄ 8 and the 13 ⁄ 8 riff of the second guitar track ( 6 ⁄ 8 + 7 ⁄ 8 = 13 ⁄ 8 ). This produces an extremely complex rhythmic overall structure and different harmonic overlays on each pass until the two guitar tracks after 91 eighth notes (13 repeats of the 7 / 8 riffs and 7 repeats of the 13 / 8 meet again riffs), d. H. the "Eins" (the first beat of a measure) is for the first time again simultaneously for both tracks. Such a polymetric requires extremely high skill from the musicians.
- The first four bars of the title Skimble of the railway (Skimbleshanks, the railway cat) from the musical Cats by Andrew Lloyd Webber are in the 13 / 8 listed -Stroke.
Notation and audio example
for an atonal, chromatic passage of polymetric music. The two guitar tracks play at first - as in the example discussed above - a unison riff, this time in the 11 / 8 -Stroke, which then an eighth note is added in the second track every other clock. Accordingly, there is a superposition of a 11 / 8 -Takts in the first track with a change of 11 / 8 - and 12 / 8 -Takten in the second track. This is a notation of the audio example, in which the different time signatures in the two tracks are classicallystandardizedto 11 ⁄ 8 . To illustrate the metric overlay, theactualmeasures of the individual tracks have been marked:
It turns out that only in the 24 11 / 8 -Stroke the first blow in the actual bars of each track with the other coincides again. The first two notated bars are still in unison, after which the overlay shifts by an eighth note every two bars, so that the tracks initially “drift apart”. Exactly at the transition from 11th to 12th of the notated measures, the tracks are furthest apart. Between the F sharp in both tracks (which always represents the beginning of the actual measure) there are now 4 or 5 (depending on “to the left” and “to the right”) eighth notes. The tracks then approach each other again to be in unison again in the notated measure 24. Based on this analysis, it can be seen that the (dis) harmonic overlays change with each pass of the 23 ⁄ 8 riff in the second voice. This results in an extremely complex overall structure of rhythm, melody and harmony.
In order to clarify the (dis-) harmonic overlays, here is a notation of the passage in which both voices are shown superimposed:
Alternatively, a polymetric passage can also be notated inconsistently, so that the actual time signature is given in the notation for each instrument. This has the disadvantage that it is no longer possible to specify a point in the piece in the form of a measure number, since within a certain period of time a part has notated more or fewer measures than another track with which it is superimposed polymetrically. For the instrumentalists, however, it has the advantage that the notation of their respective track is clearly grouped and indicates the actual time signature. This is an advantage compared to the traditional standardization, as is listed in this polymetric throughout a time signature, so that - as in the example above - in the second part a 23 / 8 -Riff ( 11 / 8 -Stroke + 12 / 8 -Stroke ) is notated as 11 ⁄ 8 , which means that an actual measure is no longer limited by two bar lines, but goes beyond the borders of these. A notation of each part in its actual time signature offers the instrumentalists a clearer structure and would make the polymetrics as such directly recognizable in a score, but would have the disadvantage that one measure number for all instruments can no longer indicate the same section in the entire piece. making the creation of a score difficult.