Pitch strength in Pink Floyd, Eminem and Meshuggah
According to the Oxford Music Online resource, sounds have either pitch or no pitch. Pitch is described as “[t]he particular quality of a sound (e.g. an individual musical note) that fixes its position in the scale. Certain sounds used in music that occupy no particular scale position, such as those produced by cymbals or the side drum, can be said to be of indefinite pitch” [Haynes and Cooke, 2001]. A similar point of view can be found in the “Pitch (music)” Wikipedia article.
Other sources, on the other hand, recognize the existence of a continuum between “no pitch” and “pitch”, which may be called “pitch strength”, “pitch saliency”, “clarity of pitch sensation” or “definition of pitch sensation”. According to [Yost, 2009], “[p]itch strength (also called pitch saliency) refers to the strength of the perceived pitch of a complex sound as compared with the overall perceived quality (timbre) of the sound (see [Patterson et al., 2000]). “ According to [Moylan, 2020], “[t]he clarity of pitch sensation (or definition of pitch sensation) is a variable, to which timbre plays a decisive role. This is not a dichotomy, but rather a continuum between the extremes represented by white noise and an uncompromised pitch sensation”. In a 2007 interview, music producer Scott Storch also attests to the existence of such a continuum, which he calls “amount of tune” (see also this article on Medium).
In the field of Music Information Retrieval, the distinction can be reflected in the output representation of chromas. For instance, [Serra et al., 2012] use pitch codewords in which for one given note, pitch is present or absent, while [Mauch et al., 2015] use vectors in which pitch can have any value between 0 and 1 for one given note.
In the present article, we show examples in which “moderate” pitch strength can be observed. In the first example, we focus on a drum part from the song Time by the British band Pink Floyd. Using the Sony CSL proprietary VST/AU plug-in Resonance EQ, we vary the drums’ pitch strength and show that with a greater pitch strength, the pitch of the drums becomes clear enough to be transcribed. We offer a possible explanation for how a moderate pitch strength can be useful for the musical discourse. In the second example, we show that a similar explanation can be used to better understand the form in the lead vocals from the track No Love by American rapper Eminem. In the third example, we show how pitch strength can be useful to characterise the semiotic structure [Bimbot et al., 2012] in the track Clockworks by Swedish metal band Meshuggah.
Pink Floyd, “Time”, performed by Roger Waters: pitch strength, dissonances
Although the track Time is originally part of the album The Dark side of the Moon, released in 1973, we choose to base the analysis on the version performed by Pink Floyd’s former member Roger Waters during the 2017–2018 Us + Them Tour, released as a movie in 2019. The choice for this version stems from the fact that in the Us + Them video, the filming provides a very good view of the musician playing the Rototom part on which we focus.
Video 1 is an annotated version of the first one minute and forty-three seconds of the song Time as performed by Roger Waters and musicians during the Us + Them tour. In this video, we draw attention to the Rototom part in particular.
Resonance EQ [Grachten et al., 2019][Deruty, 2020], is a VST plug-in developed at Sony CSL by Matthias Demoucron. The plug-in attenuates/amplifies spectral formants. As shown on the plug-in’s CSL page, one interpretation of the process is that it is similar to saturate/desaturate images. Attenuating formants whiten the audio spectrum, it is comparable to attenuating colours in an image (desaturation). Boosting formants colours the audio spectrum, it is comparable to making colours purer in an image (saturation). By attenuating/boosting formants, the process can modify the pitch strength of the audio input. Video 2 illustrates how the plug-in can enhance the pitch strength of the “tic-toc” that can be heard at the beginning of Time.
Video 3 shows the same extract as Video 1, this time with the audio processed using Resonance EQ to boost the formants. As the Rototom’s pitch strength increases, it becomes possible to transcribe the Rototom parts in a score.
Video 4 focuses on the part that can be found between 1'00 and 1'07 in Video 3. The annotated content is played back using a piano sound (high pitch strength) and then compared to the original (Rototom, lower pitch strength). In bar 3, the flat G in an F# minor context leads to dissonance. The dissonance is much more obvious in the piano rendition than in the original. The dissonance sounds attenuated by the use of a lower pitch strength. One possible interest of a lower pitch strength may therefore be the following. A lower pitch strength might make it possible to benefit from the tension brought by the dissonance, while attenuating its dissonant character. For a discussion that links the notions of “dissonance” and “tension”, see [Parncutt, 2011].
Eminem, “No Love”: pitch strength, rap vocal form and dissonances
The track No Love is part of Eminem’s album “Recovery”, released in 2010. As in many rap songs, the lead vocals appear to feature a lower pitch strength than sung parts.
Video 5 focuses on 8 bars found in the original song between 3'12 and 3'27. The 8 bars are presented three times: as such, processed with Resonance EQ (formants enhanced, pitch strength increased) and superimposed with a piano rendering of the transcribed vocals (high pitch strength). The vocals are transcribed from the version processed with Resonance EQ.
The song’s tonality is G# minor.
* Bars 1, 2 and 3: the flow revolves around C# (fourth) and D# (fifth). Those intervals are perfect consonances.
* Bar 4: flow around C# (fourth) and E (minor sixth). Perfect and imperfect consonances.
* Bar 5: flow around D natural (diminished fifth / augmented fourth) and E (minor sixth). Dissonance and imperfect consonance.
* Bars 6, 7 and 8: flow around C# (fourth) and E (minor sixth). Perfect and imperfect consonances.
For the terms “perfect consonance” and “imperfect consonance”, see [Rushton, 2001].
Observation of the intervals in each bar suggests that the vocals subscribe to the following form: 3 bars are consonant, 1 bar is less consonant, 1 bar contains dissonance, and the three last bars are as consonants as the second one. There is no tension (bars 1–3), a slight tension (bar 4), tension (bar 5), and a partial resolution to a slight tension (bars 6–8).
Listening to the audio track in Video 5, one can realise that in the version processed with Resonance EQ (higher pitch strength), the imperfect consonances and the dissonances, which were not bothering in the original, now sound a bit out of place. In the version with the rendered piano transcription, the imperfect consonances and the dissonances are truly dissonant and out of place. It suggests that similarly to what we observed in Pink Floyd’s Time, a lower pitch strength might make it possible to benefit from the tension brought by the dissonance, while attenuating its dissonant character.
Meshuggah, “Clockworks”: pitch strength as a determinant of semiotic structure
The track Clockworks is part of Meshuggah’s album “The Violent Sleep of Reason”, released in 2016. We show how in this example, pitch strength is one of the musical dimensions that determines structural boundaries.
Figure 1 shows a cursory analysis of Clockworks’ first minute. The first minute of the track is split into four semiotic segments (see [Bimbot et al., 2012] for the semiotic structure of music pieces). Segments 1 and 2 feature a guitar with a low pitch strength. Although it is possible to sort the elements played by the guitar on a scale, it is not possible to associate notes to the scale positions. Segments 3 and 4 feature a guitar with higher pitch strength. It is possible to associate notes to its playing.
Listening to the audio in Video 6, below, suggests that the new guitar’s higher pitch strength plays an important role in the characterisation of segment 3 in contrast to segment 2. In this track, pitch strength is a musical parameter characterising the semiotic structure. To borrow vocabulary from [Caplin, 2001], pitch strength here plays the role of a determinant of form (specifically semiotic structure).
Conclusions
Judging from these examples:
1) Pitch strength is a reality in contemporary Popular Music (the three examples).
2) A moderate pitch strength may be useful to attenuate dissonances while conserving the tension dissonances bring (examples 1 and 2).
3) Pitch strength can play a role to characterise structure (example 3).
4) Manipulation of pitch strength may be useful to better describe the music (examples 1 and 2).
References
[Bimbot et al., 2012] Bimbot, Frédéric, et al. “Semiotic structure labeling of music pieces: Concepts, methods and annotation conventions.” 13th International Society for Music Information Retrieval Conference (ISMIR). 2012.
[Caplin, 2001] Caplin, William E. Classical form: A theory of formal functions for the instrumental music of Haydn, Mozart, and Beethoven. Oxford University Press, 2001.
[Deruty, 2020] Deruty, Emmanuel. “Method and electronic device for formant attenuation/amplification.” European Patent EP3688754A1, Sony Europe BV United Kingdom Branch , Sony Europe BV.
[Grachten et al., 2019] Grachten, Maarten, Emmanuel Deruty, and Alexandre Tanguy. “Auto-adaptive resonance equalization using dilated residual networks.” ISMIR, 4–8 November 2019, Delft (Netherlands).
[Haynes and Cooke, 2001] Haynes, Bruce, and Peter Cooke. “Pitch.” Grove Music Online. Oxford University Press. Date of publication, 20 Jan. 2001. Date of access 3 Aug. 2022.
[Mauch et al., 2015] Mauch, Matthias, et al. “The evolution of popular music: USA 1960–2010.” Royal Society open science 2.5 (2015): 150081.
[Moylan, 2020] Moylan, William. Recording Analysis (Kindle Location 7893). Taylor and Francis. Kindle Edition.
[Parncutt, 2011] Parncutt, Richard, and Graham Hair. “Consonance and dissonance in music theory and psychology: Disentangling dissonant dichotomies.” Journal of interdisciplinary music studies 5.2 (2011).
[Patterson et al., 2000] Patterson, Roy D., et al. “The perceptual tone/noise ratio of merged iterated rippled noises.” The Journal of the Acoustical Society of America 107.3 (2000): 1578–1588.
[Rushton, 2001] Rushton, Julian. “Perfect consonance”. Grove Music Online. . Oxford University Press. Date of publication: 20 Jan. 2001. Date of access 5 Aug. 2022.
[Serra et al., 2012] Serrà, Joan, et al. “Measuring the evolution of contemporary western popular music.” Scientific reports 2.1 (2012): 1–6.
[Yost, 2009] Yost, William A. “Pitch perception.” Attention, Perception, & Psychophysics 71.8 (2009): 1701–1715.
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