1aMU6 – Psychoacoustic phenomena in electric-guitar performance

Jonas Braasch
School of Architecture, Rensselaer Polytechnic Inst.
Troy, NY 12180
braasj@rpi.edu

Joshua L. Braasch
Trans-genre Studio
Latham, NY

Torben Pastore
College of Health Solutions
Arizona State Univ
Tempe, AZ

Popular version of paper 1aMU6 Psychoacoustic phenomena in electric-guitar performance
Presented Tuesday morning, June 8, 2021
180th ASA Meeting, Acoustics in Focus

This presentation examines how electric guitar effects helped pave the road to modern rock and roll music. Distortion effects provide sustain for the guitar similar to other core-ensemble instruments like the violin and piano in classical music. Distortion can also make the sound brighter to heighten the often aggressive sound of rock music. Other effects, like the chorus, phaser, and flanger, can help make the guitar sound much wider, something we are also used to listening to with classical orchestras. To some extent, electrical guitar effects substituted for and expanded upon the room reverberation that typically accompanies classical music, and they were instrumental in producing stereo Rock ‘n’ Roll records that provide spatial width, something old mono records do not provide. While often having favorable sound-color characteristics, the sound of mono recordings sits static in between both ears when listening through headphones or earbuds. This phenomenon, which is called inside-the-head locatedness, is not apparent when listening through a loudspeaker. Without electric sound effects, the electric guitar would not have become the distinctive instrument that Jimi Hendrix, Link Wray, Chuck Berry, and others defined.


Figure 1: Schematic depicting the stereo image (left/right balance) for examplary stereo recordings. Left: In Jazz albums like Miles Davis’ Kind of Blue, placing instruments to the left, center, or right worked well because of the transparent sound ideal of the genre; Center: Early rock/pop songs like the Beatles’ “Helter Skelter” used the same approach with less success; Right: Electronic effects later made it possible to widene the instrument sounds like it is the case for Nirvana’s “Smells like teen spirit” — reflecting the genre’s sound ideal to perceptually fuse sounds together.

A brief survey was conducted to investigate the extent to which electrical sound effects provide a desirable guitar sound beyond the sustain and spatial qualities these effects can provide. The outcome for a group of 21 participants (guitarist and non-guitarists) suggests that listeners have their distinct preferences when listening to a blues solo. It appears that they prefer some but not all distortion effects over a clean, non-distorted sound.


Figure 2: Guitar effects used in the listening survey

 


Figure 3: Results of the listening survey. The average preference over 21 listener is shown as a function of 10 different guitar distortion effects that were used in the survey. Three percpetually distinct groups were found.  Two effects rated significantly higher than the other eight, and one effect was rated significantly lower than all other ones. The clean (no effect) condition was in the center group, so dependent on the type of distortion, the effect can make the guitar sound better or worth.

Speaker Update: International Year of Sound Event to Explore Acoustics of Steelpan Music

Speaker Update: International Year of Sound Event to Explore Acoustics of Steelpan Music

David Bradley unavailable; Andrew Morrison to present on making meaning from acoustical data

For More Information:
Keeta Jones
516-576-2364
kjones@acousticalsociety.org

MELVILLE, N.Y., August 5, 2020 – The Acoustical Society of America (ASA) continues to host virtual events in August as part of the International Year of Sound.

On Aug. 6, David Carreon Bradley was scheduled to present at a virtual talk, but he is unable to do so. Instead, Andrew Morrison will discuss how the acoustical physics of the steelpan helps machine learning algorithms process large datasets.

All events are open to the public, and admission is free. ASA encourages media, scientists, audio enthusiasts, students, educators and families to tune in.

Making meaning from data — from the acoustics lab to machine learning: Thursday, Aug. 6

Morrison, a professor of physics and astronomy at Joliet Junior College, was intrigued by the characteristic sound of a Caribbean steelpan drum, which is easy to recognize by ear and yet still does not have a full scientific explanation for the how this musical instrument produces the distinctive tone.

His virtual talk, “Making meaning from data — from the acoustics lab to machine learning,” starts at 1 p.m. Eastern U.S. on Aug. 6.

He will discuss what is known about the physics of the steelpan, how scientists have engaged with the public to help classify the data, and how machine learning algorithms are being used to help process large datasets. He will also discuss how this study is useful for illustrating some parts of the scientific process.

A question-and-answer period will follow.

Morrison’s research interests include using optical methods and machine learning analysis techniques to study the vibrations of musical instruments. He is a past chair of the ASA Technical Committee on Musical Acoustics, is actively involved in the ASA Committee on Education in Acoustics and has a passion for working with undergraduates in his laboratory.

Don’t forget to register for this free event at https://aipp.zoom.us/meeting/register/tJ0pd-CgqjItH9wj-nGQnxV0hEJxbtYWiR1t.

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ABOUT ACOUSTICAL SOCIETY OF AMERICA

The Acoustical Society of America is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year.

 

1pMU4: Reproducing tonguing strategies in single-reed woodwinds using an artificial blowing machine

Montserrat Pàmies-Vilà – pamies-vila@mdw.ac.at
Alex Hofmann – hofmann-alex@ mdw.ac.at
Vasileios Chatziioannou – chatziioannou@mdw.ac.at
University of Music and Performing Arts Vienna
Anton-von-Webern-Platz 1
1030 Vienna, Austria

Popular version of paper 1pMU4: Reproducing tonguing strategies in single-reed woodwinds using an artificial blowing machine
Presented Monday morning, May 13, 2019
177th ASA Meeting, Louisville, KY

Clarinet and saxophone players create sounds by blowing into the instrument through a mouthpiece with an attached reed, and they control the sound production by adjusting the air pressure in their mouth and the force that the lips apply to the reed. The role of the player’s tongue is to achieve different articulation styles, for example legato (or slurred), portato and staccato. The tongue touches the reed in order to stop its vibration and regulates the separation between notes. In legato the notes are played without separation, in portato the tongue shortly touches the reed and in staccato there is a longer silence between notes. A group of 11 clarinet players from the University of Music and Performing Arts Vienna (Vienna, Austria) tested these tonguing techniques with an equipped clarinet. Figure 1 shows an example of the recorded signals. The analysis revealed that the portato technique is performed similarly among players, whereas staccato requires tonguing and blowing coordination and it is more player-dependent.

Figure 1: Articulation techniques in the clarinet, played by a professional player. Blowing pressure (blue), mouthpiece sound pressure (green) and reed displacement (orange) in legato, portato and staccato articulation. Bottom right: pressure sensors placed on the clarinet mouthpiece and strain gauge on a reed.

The interest of the current study is to mimic these tonguing techniques using an artificial setup, where the vibration of the reed and the motion of the tongue can be observed. The artificial setup consists of a transparent box (artificial mouth), allowing to track the reed motion, the position of the lip and the artificial tongue. This artificial blowing-and-tonguing machine is shown in Figure 2. The build-in tonguing system is controlled with a shaker, in order to assure repeatability. The tonguing system enters the artificial mouth through a circular joint, which allows testing several tongue movements. The parameters obtained from the measurements with players are used to set up the air pressure in the artificial mouth and the behavior of the tonguing system.

Figure 2: The clarinet mouthpiece is placed through an airtight hole into a Plexiglas box. This blowing machine allows monitoring the air pressure in the box, the artificial lip and the motion of the artificial tongue, while recording the mouth and mouthpiece pressure and the reed displacement.

The signals recorded with the artificial setup were compared to the measurements obtained with clarinet players. We provide some sound examples comparing one player (first) with the blowing machine (second). A statistical analysis showed that the machine is capable of reproducing the portato articulation, achieving similar attack and release transients (the sound profile at the beginning and at the end of every note). However, in staccato articulation the blowing machine produces too fast release transients.

Comparison between a real player and the blowing machine.

This artificial blowing and tonguing set-up gives the possibility to record the essential physical variables taking part in the sound production and helps into the better understanding of the processes taking place inside the clarinetist’s mouth during playing.

4aMU6 – How Strings Sound Like Metal: The Illusion of the Duck-Herders Musical Cape

Indraswari Kusumaningtyas – i.kusumaningtyas@ugm.ac.id
Gea Parikesit – gofparikesit@ugm.ac.id

Faculty of Engineering, Universitas Gadjah Mada
Jl. Grafika 2, Kampus UGM
Yogyakarta, 55281, INDONESIA

Popular version of paper 4aMU6, “Computational analysis of the Bundengan, an endangered musical instrument from Indonesia”
Presented Thursday morning, May 10, 2018, 10:00-10:15 AM, Lakeshore A
175th ASA Meeting, Minneapolis, MN

Bundengan is an endangered musical instrument from Indonesia. It has a distinctive half-dome structure, which is originally built by duck herders and used as a cape to protect themselves from adverse weather when tending their flocks. To pass their time in the fields, the duck herders play music and sing. The illusive sound of the bundengan is produced by plucking a set of strings equipped with small bamboo clips and a number of long, thin bamboo plates fitted on the resonating dome; see Figure 1. The clipped strings and the long, thin bamboo plates allow the bundengan to imitate the sound of the gongs and kendangs (cow-hide drums) in a gamelan ensemble, respectively. Hence, it is sometimes referred to as the poor-man’s gamelan. Examples of the bundengan sound can be found from: http://www.auralarchipelago.com/auralarchipelago/bundengan.

Kusumaningtyas Parikesit – Figure 1. Construction of the bundengan 300 dpi.jpeg
Figure 1. The construction of the bundengan (left). A set of strings with small bamboo clips and a number of long, thin bamboo plates are fitted on the grid (right).

Amongst the components of the bundengan, arguably the most intriguing are the strings. We use computational simulations to investigate how the clipped strings produce the gong-like sound. By building a finite element model of a bundengan string, we visualize how the string vibration changes when the number, size (hence mass), and position of the bamboo clips are varied.

We first simulate the vibration of a 20 cm string, first with no bamboo clip and then with one bamboo clip placed at 6 cm from one of its end. Compared to the string with no clip (Figure 2a), the addition of the bamboo clip alters the string vibration (Figure 2b), such that two vibrations of different frequencies emerge, each located at different sections of the string divided by the bamboo clip. A relatively high frequency vibration occurs at the longer part of the string, whereas a relatively low frequency vibration occurs at the shorter part of the string. This correlates well with our high-speed recording of the bundengan string vibration; see http://ugm.id/bundengan.

Kusumaningtyas Parikesit - Figure 2. Bundengan string without and with clip 300 dpi.jpeg
Figure 2. Contour plot of the bundengan string vibration when plucked at the centre of the string for (a) no bamboo clip, and (b) one bamboo clip located at 0.06 m.

We also simulate how the position of the bamboo clip affect the frequencies of the string vibration and, hence, the sound produced by the clipped string. Figure 3 demonstrates that, for the string with a bamboo clip, we have two strong peaks at frequencies lower and higher than the frequency of the peak when there is no clip. The magnitudes of these two peaks change as the clip is shifted away from the end of the string, changing the pitch of the sound.

Kusumaningtyas Parikesit - Figure 3. Frequency spectrum 300 dpi.jpegFigure 3. Frequency spectra of the bundengan string vibration when the location of the bamboo clip is shifted from 1 cm to 9 cm from one end of the 20 cm string. The spectrum for the string with no clip is also given (top graph).

In a bundengan string equipped with bamboo clip, the emergence of the two different-frequency vibrations at different sections of the string is the key to the production of the gong-like sound. The vibration spectra allow us to understand the tuning of the bundengan string due to the position of the bamboo clip. This can serve as a guide to design the bundengan, providing possibilities for future developments.

 

List of Figures.
Kusumaningtyas Parikesit – Figure 1. Construction of the bundengan 300 dpi.jpeg 
Kusumaningtyas Parikesit – Figure 2. Bundengan string without and with clip 300 dpi.jpeg
Kusumaningtyas Parikesit – Figure 3. Frequency spectrum 300 dpi.jpeg

3aMU8 – Comparing the Chinese erhu and the European violin using high-speed camera measurements

Florian Pfeifle – Florian.Pfeifle@uni-hamburg.de

Institute of Systematic Musicology
University of Hamburg
Neue Rabenstrasse 13
22765 Hamburg, Germany
Popular version of paper 3aMU8, “Organologic and acoustic similarities of the European violin and the Chinese erhu”
Presented Wednesday morning, November 30, 2016
172nd ASA Meeting, Honolulu

0. Overview and introduction
Have you ever wondered what a violin solo piece like Paganini’s La Campanella would sound like if played on a Chinese erhu, or how an erhu solo performance of Horse Racing, a Mongolian folk song, would sound on a modern violin?

Our work is concerned with the research of acoustic similarities and differences of these two instruments using high-speed camera measurements and piezoelectric pickups to record and quantify the motion and vibrational response of each instrument part individually.
The research question here is, where do acoustic differences between both instruments begin and what are the underlying physical mechanisms responsible?

1. The instruments
The Chinese erhu is the most popular instrument in the bowed string instrument group known as huqin in China. It plays a central role in various kinds of classical music as well as in regional folk music styles.  Figure 1 shows a handcrafted master luthier erhu.  In orchestral and ensemble music its role is comparable to the European violin as it often takes the role as the lead voice instrument.

A handcrafted master luthier erhu. This instrument is used in all of our measurements.

Figure 1. A handcrafted master luthier erhu. This instrument is used in all of our measurements.

In contrast to the violin, the erhu is played in anupright position, resting on the left thigh of the musician. It consists of two strings, as compared to four in the case of the violin. The bow is put between both strings instead of being played from the top as European bowed instruments are usually played. In addition to the difference in bowing technique, the left hand does not stop the strings on a neck but presses the firmly taut strings, thereby changing their freely vibrating length.  A similarity between both instruments is the use of a horse-hair strung bow to excite the strings.  The history of an instrument similar to the erhu is documented from the 11th century onwards, in the case of the violin from the 15th century. The historic development before that time is still not fully known, but there is some consensus between most researchers that bowed lutes have their origin in central Asia, presumably somewhere along the silk road. Early pictorial sources point to a place of origin in an area known as Transoxiana which spanned an area across modern Uzbekistan and Turkmenistan.

Comparing instruments from different cultural spheres and having different backgrounds is a many-faceted problem as there are historical, cultural, structural and musical factors playing an important role in the aesthetic perception of an instrument. Measuring and comparing acoustical features of instruments can be used to objectify this endeavour, at least to a certain degree.  Therefore, the method applied in this paper aims at finding and comparing differences and similarities on an acoustical level, using different data acquisition methods.  The measurement setup is depicted in Figure 2.

Measurement setup for both instrument measurements.

Figure 2. Measurement setup for both instrument measurements.

The vibration of the strings are recorded using a high-speed camera which is able to capture the deflection of bowed strings with a very high frame rate.  An exemplary video of such a measurement is shown in Video 1.

Video 1.  A high-speed recording of a bowed violin string.

The recorded motion of a string can now be tracked with sub-pixel accuracy using a tracking software that traces the trajectory of a defined point on the string. The motion of the bridge is measured by applying a miniature piezoelectric transducer, which converts microscopic motions into measurable electronic signals, to the bridge. We record the radiated instrument sound using a standard measurement microphone which is positioned one meter from the instrument’s main radiating part. This measurement setup results in three different types of data: first only the bowed string without the influence of the body of the instrument; the motion of the bridge and the string; and a recording of the radiated instrument sound under normal playing conditions.

Returning to the initial question, we can now analyze and compare each measurement individually. What is even more exciting, we can combine measurements of the string deflection of one instrument with the response of the other instrument’s body. In this way we can approximate the amount of influence the body has on the sound colour of the instrument and if it is possible to make an erhu performance sound like a violin performance, or vice versa. The following sound files convey an idea of this methodology by combining the string motion of part of an Mongolian folk song played on an erhu with the body of an European violin. Sound-example 1 is a microphone recording of the erhu piece and sound-example 2 is the same recording using only the string measurement combined with an European violin body.  To experience the difference clearly, headphones or reasonably good loudspeakers are recommended.

Audio File 1. A section of an erhusolo piece recorded with a microphone.

Audio File 2. A section of the same erhupiece combining the erhu string measurement with a violin body.

2. Discussion
The results clearly show that the violin body has a noticeable influence on the timbre, or quality, of the piece when compared to the microphone recording of the erhu. But even so, due to the specific tonal quality of the piece itself, it does not sound like a composition from an European tradition. This means that stylistic and expressive idiosyncrasies are easily recognizable and influence the perceived aesthetic of an instrument. The proposed technique could be used to extend the comparison of other instruments, such as plucked lutes like the guitar and pi’pa, or mandolin and ruanxian.