Related Experiment Video
Updated: Aug 12, 2026
05:48
Memorization-Based Training and Testing Paradigm for Robust Vocal Identity Recognition in Expressive Speech Using Event-Related Potentials Analysis
Published on: August 9, 2024
Speech enhancement by filtering in the loudness domain
1Drittes Physikalisches Institut, Universität Göttingen, Fed. Rep. of Germany.
Acta Oto-Laryngologica. Supplementum
|January 1, 1990
Summary
Loudness compensation improved speech intelligibility for hearing-impaired individuals by optimizing gain. Enhancing dynamic intensity modulations did not significantly affect speech discrimination in quiet or noisy environments.
Area of Science:
- Audiology
- Speech processing
- Hearing aid technology
Background:
- Previous attempts using dynamic compression for cochlear impairment and recruitment failed to enhance speech intelligibility.
- A key factor is the attenuation of dynamic intensity modulations (1-50 Hz), crucial for speech discrimination.
Purpose of the Study:
- To investigate an approach enhancing, rather than attenuating, dynamic intensity modulations using an envelope highpass filter in the loudness domain.
- To simulate a digital hearing aid tailored to individual loudness scaling functions.
Main Methods:
- Filterbank processing to extract and manipulate the envelope signal.
- Conversion to loudness, highpass filtering, and reconversion to the desired envelope based on individual hearing impairment.
- Amplitude correction and summation of filterbank channel outputs.
Main Results:
- Loudness compensation without highpass filtering improved speech intelligibility across various input levels.
- An optimum gain characteristic was achieved at all input levels with loudness compensation.
- The highpass filter applied to the envelope showed no significant effect on speech discrimination in quiet or noise.
Conclusions:
- Loudness compensation is effective in improving speech intelligibility for hearing-impaired individuals.
- Enhancing dynamic intensity modulations via loudness domain highpass filtering does not further benefit speech discrimination.
- The developed algorithm shows potential for digital hearing aid applications.
Related Concept Videos
00:58Sound Intensity
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 emitted...
00:53Sound Intensity Level
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 hence a...
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 hence a...
01:27Passive Filters
Passive filters are utilized to shape the frequency spectrum of signals across a diverse array of applications. These filters, using only passive elements like resistors (R), inductors (L), and capacitors (C), are capable of selectively allowing or blocking certain frequency ranges without the need for external power sources.
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff frequency...
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff frequency...
01:25Active Filters
Active filters are electronic circuits that use operational amplifiers (op-amps), resistors, and capacitors to filter out unwanted frequency components from a signal. A first-order low-pass active filter is designed to pass signals with a frequency lower than a certain cutoff frequency and attenuate frequencies higher than that cutoff frequency. The transfer function for a first-order low-pass active filter is:
01:23Design Example
The innovation of touch-tone telephony revolutionized the telecommunications industry by replacing the traditional rotary dial with a dual-tone multi-frequency (DTMF) signaling system. This system uses a matrix-style keypad with buttons arranged in four rows and three columns, creating 12 distinct signals each assigned to a pair of frequencies. Each button press results in a simultaneous generation of two sinusoidal tones – one from a low-frequency group (697 to 941 Hz) and one from a...
01:21Perceiving Loudness, Pitch, and Location
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 identifying...
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 identifying...