At the end of the 1950s and in the early 1960s, in Penderecki's post student years, he sought out new sonic and technical possibilities of instruments, particularly for strings,[1] by unconventional means of articulation and peculiar treatment of sound-pitch.

This timbre organization was based on the simple explanation that the process of generating the acoustic wave is simply the “collision of two physical bodies, one being a sound source, the other being the body that vibrates the sound source.”[4] Penderecki most likely derived his timbre organization from the teaching of Mieczyslaw Drobner, a Polish acoustician and organologist who in 1958 obtained the post of lecturer at the school where Penderecki had recently finished studying and was employed as an assistant.

Because Penderecki understood timbre primarily as a function of the materials, the timbral categories in his sonorism are based upon the most common materials used in the assembly of instruments and accessories of traditional symphonic orchestras: metal, wood, leather, felt, and hair.

This then means that at least one of the two sound-generating bodies must be made of metal, wood, or leather, referred to as primary materials.

Though he was inspired by Drobner, Penderecki’s timbre system goes another step further, in which “it is of no importance whether metal, wood, and leather are represented by a vibrator or by an inciter, both colliding bodies being of equal weight as primary materials.”[4] This means that “if a given body can be a sound source—that is, if it is made of one of the three materials capable of performing this function (m, w, l) --then it becomes a sound source regardless of whether it is hit, rubbed or plucked or itself hits, rubs or plucks.”[4] Though Penderecki’s timbre system used material categories found in the traditional symphonic orchestra, he had to employ drastic changes to produce the desired effects.

Since the piece is written solely for stringed instruments, Penderecki used a variety of methods to create opposing sections of metal and wood.

It contains such percussive techniques as; battuto col legno (strike the strings with the wood of the bow); taps con dita (with fingers) between the bridge and tailpiece; pizzicato and pizzicato con due dita (plucked with two fingers).

This serves as a coda as well as a kind of release of the tension created by the microtones and unfamiliar timbral effects of the composition.

[5] In a 1977 interview with Composer magazine, Penderecki claimed that the C major chord was the seed from which the entire composition grew.

[5] Adrian Thomas interprets Penderecki's claim as "theoretically arguable and indeed the preceding emphases on certain pitch classes and the open clusters may retrospectively be seen to augur such a conclusion.

The value of the C major triad lies not in any putative harmonic consequentiality that confirms a traditional process but in its radical challenge to what Penderecki had established as his norms.

[7] In some sections of the work, the temporal processes within the sonoristic system become complex, with multiple entrances in several instrumental parts.

[7] This technique makes possible the proper communication of details of this highly complex passage of clusters in Polymorphia.

Penderecki communicates many of his timbral effects via means much more pictorial than in traditional Western music notation.

It is essentially a more advanced version of the system used in the Threnody for the Victims of Hiroshima, and it is further developed in the 1962 work Fluorescences.

[1] Another effect instructs the performer to “tap the desk with the bow or the chair with the heel.”[7] Here, Penderecki turns traditionally non-musical items into instruments which are included in the work.

At rehearsal eight in the basses, Penderecki uses a symbol resembling a long band of intersecting sound waves to represent a glissando passage.