3pEA6 – Selective monitoring of noise emitted by vehicles involved in road traffic

Andrzej Czyżewski
Gdansk University of Technology
Multimedia Systems Department
80-233 Gdansk, Poland
www.multimed.org
E-mail: ac@pg.edu.pl

Tomasz Śmiałkowski
SILED Co. Ltd.
83-011 Gdańsk Poland
http://siled.pl/en/
E-mail: biuro@siled.pl

Popular version of paper 3pEA6 Selective monitoring of noise emitted by vehicles involved in road traffic
Presented Thursday afternoon, June 10, 2021
180th ASA Meeting, Acoustics in Focus

The aim of the project carried out by a Gdansk University of Technology in cooperation with an electronics company is to conduct industrial research, development, and pre-implementation works on a new product, namely an intelligent lighting platform.  This kind of street lamp system called infoLIGHT using a new generation of LEDs will become a smart city access point to various city services (Fig. 1).

Figure 1 Intelligent lighting platform – infoLIGHT project website

The research focuses on the electronics built in the street lamp using multiple sensors (Fig. 2), including an acoustic intensity probe that measures the sound intensity in three orthogonal directions, making it possible to calculate the azimuth and elevation angles, describing the sound source position.

Figure 2 – Road lamp design

The acoustic sensor is made in the form of a cube with a side of 10 mm, on the inner surfaces of which the digital MEMS microphones are mounted (Fig. 3). The acoustic probes were mounted on the lamp posts that illuminate the roadways depending on the volume of traffic.

Figure 3 Acoustical vector sensor – construction

The algorithm works in two stages. The first stage is the analysis of sound intensity signals to detect acoustic events. The second stage analyses acquired signals based on the normalized source position; its task is to determine whether the acoustic event represents what kind of a vehicle passing the sensor and detecting its movement direction. A neural network was applied for selective analysis of traffic noise (Fig. 4). The neural network depicted in Figure 4 is the so-called 1D (one-dimensional) convolution neural network. It was trained to count vehicles passing by through the analysis of noise emitted by them.

Figure 4 Neural network applied for selective analysis of traffic noise

The paper presented at the ASA Meeting explains how accurately traffic can be monitored through directional noise analysis emitted by vehicles and shows the resulting application to smart cities (see Fig. 5).

Figure 5 Comparative results of traffic analysis employing various approaches

The Polish National Centre for Research and Development (NCBR) subsidizes project No. POIR.04.01.04/2019 is entitled: infoLIGHT – “Cloud-based lighting system for smart cities” from the budget of the European Regional Development Fund.

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.

1aSC1 – Untangling the link between working memory and understanding speech

Adam Bosen – adam.bosen@boystwon.org
Boys Town National Research Hospital
555 N. 30th St
Omaha, NE 68131

Popular version of paper 1aSC1 Reconsidering reading span as the sole measure of working memory in speech recognition research
Presented Tuesday morning, June 8th, 2021
180th ASA Meeting, Acoustics in Focus

Many patients with cochlear implants have difficulty understanding speech. Cochlear implants often do not convey all of the pieces of speech, so the patient often has to use their memory of what they heard to fill in the missing pieces. As a result, their ability to understand speech is correlated with their performance on working memory tests (O’Neill et al., 2019). Working memory is our ability to simultaneously remember some information while working on other information. For example, if you want to add 57 and 38 in your head you need to sum 7+8 and then hold the result in memory while you work on summing 50+30.

The reading span test is a common tool for measuring working memory. In this test, people see lists of alternating sentences and letters and must decide whether each sentence makes sense while simultaneously remembering the letters. The reading span test is important because it often predicts how well people with hearing loss can understand speech.

We do not know is why the reading span test is related to speech understanding. One idea is that the ability to simultaneously remember and work on interpreting what you heard is essential for understanding unclear speech. To test this idea, our lab asked young adults with normal hearing to try to understand unclear sentences. These sentences were mixed with two other people talking in the background and then processed to mimic the limited signal a cochlear implant provides.

[Vocoded Speech in Babble.mp3, An unclear recording of someone saying “If the farm is rented, the rent must be paid” with other people talking in the background.]

They also completed memory tests which do not require them to work on anything, such as remembering lists of spoken numbers (example) or words on a screen (example). These tests were as good as reading span at predicting how well these participants could understand unclear speech. This finding indicates that the reading span test is just one way to assess the parts of memory that relate to understanding speech. We conclude that the ability to simultaneously remember and work on information is not the only part of memory that helps us understand unclear speech.

We also tested older adults with cochlear implants on their ability to understand sentences and their ability to remember lists of numbers. Surprisingly, we did not find a relationship between remembering lists of numbers and understanding speech like we did in young adults with normal hearing. This finding indicates that age and/or hearing loss change which parts of working memory relate to understanding speech. Previous work suggests that some parts of working memory tend to decline with age, while others do not (Bopp & Verhaeghen, 2005; Oberauer, 2005). We conclude that further untangling the link between working memory and understanding speech requires measuring different parts of memory using multiple tests.

Bopp, K. L., & Verhaeghen, P. (2005). Aging and Verbal Memory Span: A Meta-Analysis. Journal of Gerontology, 60B(5), 223–233. https://doi.org/https://doi.org/10.1093/geronb/60.5.P223

O’Neill, E. R., Kreft, H. A., & Oxenham, A. J. (2019). Cognitive factors contribute to speech perception in cochlear-implant users and age-matched normal-hearing listeners under vocoded conditions. The Journal of the Acoustical Society of America, 146(1), 195–210. https://doi.org/10.1121/1.5116009

Oberauer, K. (2005). Control of the contents of working memory – A comparison of two paradigms and two age groups. Journal of Experimental Psychology: Learning Memory and Cognition, 31(4), 714–728. https://doi.org/10.1037/0278-7393.31.4.714

 

1aMU4 – In search of huge sound… or huge strings, at least

Pawel Bielski – pawbiels@pg.edu.pl
Hanna Pruszko – hanprus1@pg.edu.pl
Tomasz Mikulski – tomi@pg.edu.pl
Gdansk University of Technology
Narutowicza 11/12, 80-233 Gdansk
Poland

Popular version of paper 1aMU4 Numerical and experimental assessment of string gauge influence on guitar tone
Presented Tuesday morning, June 08, 2021
180th ASA Meeting, Acoustics in Focus

Meet Adam. Adam loves the nines (that is, 0.09-inch gauge, or 9’s, named by the diameter of the high E string). When he touches a guitar stringed with the 9’s, it seems soft and responsive under his fingers. This phenomenon is called “feel”. Adam picks a guitar with a proper feel and unites with the instrument. Suddenly physical bounds disappear. Adam believes in supernatural traits of the 9’s and no research can change his mind.

But we can still try.

Guitar players are obsessed with string gauges. From the super slinky 7’s of Billy Gibbons, through the agile 8’s and 9’s of Jimi Hendrix and Jimmy Page, massive sound of Joe Bonamassa (11) and Stevie Ray Vaughan (13), to Pat Martino’s super fat 15’s and extreme twang of Dick Dale (16’s). A wide selection of string gauges covers a variety of guitar playing styles.

Thicker strings are harder to bend but carry more force. Vibration is essentially very fast bending in different modes (shapes) – 1st harmonic (fundamental) and upper harmonics (overtones). Harmonic composition is called the brightness of the string. Higher harmonics create a sharp and open sound. Lower harmonics help to beef up the tone. Definition of chords also benefits from profound fundamentals.

strings

Fundamental mode and upper harmonics of a vibrating string [Source image: Harmonics.png]

Depending on the gauge, the total force carried by electric guitar strings ranges from the weight equivalent of a ten-year-old child to an adult man. It makes nearly triple the difference. Acoustic guitars offer a more humble selection of 10’s – 13’s string gauges, but the choice might be even more critical. The acoustic sound is raw and less processed. It depends on the physical features of the instrument. Fiddling with the pulling force and vibrating mass on a resonant guitar body must make a difference. The body gets tenser and stiffer. It is driven hard and significantly deformed. Will it be able to breathe freely?

Imagine borrowing your general practitioner’s stethoscope and listening to the acoustic guitar’s soundboard while it plays. This is roughly how we used accelerometers. Low E strings of different gauges were repeatedly tested for their volume, sustain (duration of sound), and harmonic composition. The samples were recorded with a microphone too. We analyzed the sound spectrum during different stages of the sound.

Setup of accelerometers [Source image: AccSetup.png]

Most findings agree with the general beliefs regarding string gauges besides one major exception. The weak sustain of heavy strings might be a surprise to many guitar players. Thick strings have a rich and loud attack yet immediately lose their superb qualities. They seem to excel at quick, punchy notes, but struggle with slow-paced singing solos. In the long run, light strings were more sustainable, retaining their harmonics in time.

[Recording of 13’s string: E6nr13.mp3]

[Recording of 10’s string: E6nr10.mp3]

Recordings of heavy and light strings (flanger effect caused by averaging from multiple samples

Advantages of the different gauges shown at two scales [Source image: Signals.png]

Other than that, heavy strings are generally louder and more substantial, while light strings seem brighter and more open. Thick strings excite the body modes (structural vibration) more, while light ones favor air resonance.

Adam will probably not readjust his beliefs, but maybe you will?

Summary of the findings

3pSCb1 – Sound Teaching Online During COVID19

Anne C. Balant – balanta@newpaltz.edu
State University of New York at New Paltz
1 Hawk Dr.
New Paltz, NY 12561

Popular version of lightening round talk 3pSCb1 “Lab kits for remote and socially distanced instruction in a GE Acoustics Course“
Presented Thursday afternoon, June 10, 2021
180th ASA Meeting, Acoustics in Focus
Read the article in Proceedings of Meetings on Acoustics

How do you give students in an online acoustics course a hands-on lab experience?

kit

At the State University of New York (SUNY) at New Paltz, students in the online sections of “The World of Sound” use a lab kit that was designed by the instructor. Students pay for shipment of the kits to their homes at the start of the course and return them at the end. They submit photos or videos of their activities along with their completed lab reports.

These kits had been in use for several years in an online post-baccalaureate program that prepares students for graduate study in speech-language pathology when the COVID19 pandemic radically changed the undergraduate on-campus version the course.

“The World of Sound” is a four-credit general education lab science course. Undergraduates typically work in groups of three and share equipment within and across lab sections. By summer of 2020, it was clear that on-campus labs in the upcoming fall semester would have to meet social distancing requirements, with no sharing of materials, and that there could be a pivot to fully remote instruction at any time. The cost of the needed individual instructional materials was a consideration due to the fiscal impact of COVID19. A revised lab kit was developed that contains everything needed for seven labs, costs under $30.00, and has a shipping weight of less than two pounds.

kit

About one-fourth of the undergraduates in the course chose to study fully remotely during fall 2020. These students had their kits shipped to them and they attended a weekly virtual lab session. Each student in the seated course was issued an individual lab kit in a shipping box that was addressed to the department for ease of return shipment. Seated labs were conducted with all required precautions including face coverings and social distancing. The kits contained everything needed for each lab, including basic supplies, so no equipment had to be shared.

Although the college was able to keep COVID19 rates low enough to stay open for the entire semester, about 15% of the students in the course transitioned to remote learning at least briefly for reasons such as illness or quarantine, missing a required covid test date, financial issues, or COVID19-related family responsibilities or crises. Having their lab kits in their possession allowed these students to move seamlessly between seated and virtual lab sessions without falling behind. Every undergraduate who studied remotely for part or all of the semester completed the course successfully.