Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Perception of Sound Waves01:01

Perception of Sound Waves

5.8K
The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...
5.8K
Echo01:06

Echo

1.0K
The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More than this, and they are perceived as separate sources.
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...
1.0K
Sound as Pressure Waves01:17

Sound as Pressure Waves

4.6K
Sound waves, which are longitudinal waves, can be modeled as the displacement amplitude varying as a function of the spatial and temporal coordinates. As a column of the medium is displaced, its successive columns are also displaced. As the successive displacements differ relatively, a pressure difference with the surrounding pressure is created. The gauge pressure varies across the medium.
The pressure fluctuation depends on the difference in displacements between the successive points in the...
4.6K
Sound Intensity Level00:53

Sound Intensity Level

4.9K
Humans perceive sound by hearing. The human ear helps sound waves reach the brain, which then interprets the waves and creates the perception of hearing. The loudness of the environment in which a person is located determines whether they can distinguish between different sound sources.
The human ear can perceive an extensive range of sound intensity, necessitating the use of the logarithmic scale to define a physical quantity—the intensity level. It is a ratio of two intensities and...
4.9K
Sound Intensity00:58

Sound Intensity

4.9K
The loudness of a sound source is related to how energetically the source is vibrating, consequently making the molecules of the propagation medium vibrate. To measure the loudness of a source, the physical quantity of interest is the intensity. This is defined as the energy emitted per unit of time per unit of area perpendicular to the sound wave's propagation direction. Since the total energy is greater if the source vibrates for a longer duration and over a larger area, dividing the...
4.9K
Perceiving Loudness, Pitch, and Location01:21

Perceiving Loudness, Pitch, and Location

1.1K
The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by...
1.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same journal

Cluster assisted soft-landing hub (CLASH): An instrument for surface desorption and deposition using a pulsed cluster ion source.

The Review of scientific instruments·2026
Same journal

Influence of pre-ionization parameters on multi-channel discharge characteristics of field-distortion switch gaps.

The Review of scientific instruments·2026
Same journal

A Joule-Thomson low-temperature scanning tunneling microscope with vector magnet and rotatable scanning head.

The Review of scientific instruments·2026
Same journal

Fiber-optic triggering of a two-stage high-current linear transformer driver with laser energy below 100 μJ.

The Review of scientific instruments·2026
Same journal

Optimization of laboratory-scale x-ray absorption spectroscopy (XAS) apparatus for nuclear fuel research.

The Review of scientific instruments·2026
Same journal

Compressed multi-scale entropy and its application in mechanical fault diagnosis.

The Review of scientific instruments·2026
See all related articles

Related Experiment Video

Updated: Feb 19, 2026

Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention
04:32

Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention

Published on: December 20, 2024

923

Second sound tracking system.

Jihee Yang1, Gary G Ihas1, Dan Ekdahl1

  • 1Department of Physics, University of Florida, Gainesville, Florida 32611, USA.

The Review of Scientific Instruments
|November 3, 2017
PubMed
Summary
This summary is machine-generated.

This study introduces a novel tracking system for superfluid helium-4 (He ii) second sound. The system reliably measures signals, outperforming fixed-frequency methods by reducing correlation with temperature fluctuations.

More Related Videos

Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication
10:28

Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication

Published on: June 5, 2016

23.5K
A Method to Study Adaptation to Left-Right Reversed Audition
07:14

A Method to Study Adaptation to Left-Right Reversed Audition

Published on: October 29, 2018

6.9K

Related Experiment Videos

Last Updated: Feb 19, 2026

Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention
04:32

Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention

Published on: December 20, 2024

923
Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication
10:28

Recording Mouse Ultrasonic Vocalizations to Evaluate Social Communication

Published on: June 5, 2016

23.5K
A Method to Study Adaptation to Left-Right Reversed Audition
07:14

A Method to Study Adaptation to Left-Right Reversed Audition

Published on: October 29, 2018

6.9K

Area of Science:

  • Experimental Physics
  • Fluid Dynamics
  • Quantum Fluids

Background:

  • Physical systems often exhibit resonance at frequencies dependent on time-varying parameters.
  • Tracking these changing frequencies and improving signal-to-noise ratio are crucial in scientific research.
  • Lock-in amplifiers are standard tools for enhancing signal quality in measurements.

Purpose of the Study:

  • To develop and present a complete Helium II (He ii) second sound system for tracking time-varying resonant frequencies.
  • To utilize automatic gain control and a lock-in amplifier for precise signal generation and demodulation.
  • To apply this tracking system to investigate turbulent decay in superfluid helium-4.

Main Methods:

  • A positive feedback system was employed to generate a stable sinusoidal signal with automatic gain control.
  • This signal was used to create temperature/entropy waves (second sound) in superfluid helium-4 (He ii).
  • A lock-in amplifier was integrated to control oscillation frequency and demodulate the received signal.

Main Results:

  • The developed tracking system demonstrated reliable measurement of second sound signals in He ii.
  • Turbulent decay in He ii was successfully probed using the second sound tracking system.
  • The tracking system showed less correlation with temperature (frequency) fluctuations compared to fixed-frequency methods.

Conclusions:

  • The presented He ii second sound system offers a more reliable method for tracking signals with changing frequencies.
  • This advanced tracking capability enhances the study of dynamic phenomena in superfluid systems.
  • The system's improved reliability over conventional methods facilitates more accurate scientific investigations.