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Siemens Stiftung

Speech signal - individual word

Chart:
Screenshot of the oscillographic curve of the spoken word "dogs".

Speech sounds are fluctuating sound signals where the composition of frequencies changes all the time.
Aperiodical overlap periodical parts. Unlike noises, some of which have similar frequency curves, sound in speech is always the carrier of meaning or of messages sent out by the speaker. Other noises like smacking of lips, hissing, rhythms, basic pitch are typical of the individual (acoustic fingerprint) but not essential for the speech content!

Information and ideas:
Supplementary to worksheets and transparencies.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves
Communication and understanding

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Siemens Stiftung

Sound diffraction

Graphic:
Diffraction is a typical feature of sound waves when they meet an obstacle.

The diffraction of sound waves is a physical mechanism which ensures the entry of sound waves into acoustic shadows.
That means the sound is audible in areas which are cut off from the direct sound incidence, such as behind obstacles.

Information and ideas:
Diffraction of light can be proved when a parallel ray beam of monochrome light is directed at a narrow opening. A screen set up behind the opening gives us a diffraction figure (bright and dark stripes that lose intensity the further outwards they are). With sound, a direct reference to the students' everyday world is even easier: Why can you hear noise from a street in front of a building even when you are behind the building?
Further information about this graphic is provided as an information sheet on the media portal of the Siemens Stiftung.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves

Medientypen

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Lernalter

13-18

Schlüsselwörter

Chart Optics Sound Wave (physics)

Sprachen

Englisch

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Siemens Stiftung

Auditory path - brain parts hearing

Labeled graphic:
"Auditory pathway? describes route taken by auditory nerve impulses in and through the brain. But the hearing process is not over yet.

The auditory pathway is the nerve tract for the sensation of hearing.
People used to think that the senses were more localised. Now we know that apart from the auditory pathway, lots of other parts of the brain are involved, too - parts that are also used by the other senses. It is this that makes it possible for human intelligence to understand abstract concepts beyond the mere recognition of patterns. To be able to understand the complex facts of a complex sentence does, after all, involves more than recognizing the words together.

Information and ideas:
Further information regarding this graphic is available as information sheet on the media portal of the Siemens Stiftung.

Relevant for teaching:
Reception and processing of information
Perception, recognition, action

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Siemens Stiftung

The Ear, Hearing and Hearing Impairment: Cochlea - individual coil section

Labeled graphic:
Section of individual coil of spiral canal of the cochlea.

The labeled graphic shows a section of an individual coil of the cochlea.

The following are labeled: scala vestibuli, tectorial membrane, hair cells of the sensory cells, spiral canal of the cochlea, auditory nerve, scala tympani.

Information and ideas:
Can be used on a worksheet, as an overhead transparency or via digital projector.
Further information regarding this graphic is available as information sheet on the media portal of the Siemens Stiftung.

Relevant for teaching:
The human body
Structure and functions of a sensory organ
Reception of stimuli and transmission of information
Functions of senses

Medientypen

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Lernalter

11-18

Schlüsselwörter

Anatomy (human) Chart Ear Sound

Sprachen

Englisch

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Siemens Stiftung

Sound refraction

Schematic diagram:
Sound refraction in air with different temperature layers (from warm to cold).

The speed of sound in the air depends on the density and thus the temperature of the air: At high temperatures, the sound travels faster than it does at lower ones. So when sound moves from a warm layer of air to a colder one, its speed decreases.
However, the direction in which the sound spreads also changes as the speed changes. It is said that the sound wave is "broken?. In the case described, i.e. when sound moves from a warm to a cold layer of air, the sound wave is broken upwards.

Information and ideas:
How does sound behave when it moves from a colder to a warmer layer?
Is it correct that you hear worse against the wind than with the wind?
The latter can be checked together with students in an experiment.
A comparison with the refraction of light rays can be made.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves

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Siemens Stiftung

The Ear, Hearing and Hearing Impairment;: Vibrations and waves

Overview graphic:
Overview of the most important parameters of vibrations and waves.

Electromagnetic waves are vibrations in the electrical and magnetic field that propagate through space at the speed of light. The parameters of vibrations and waves, such as frequency, are presented in an overview.

Instructions and ideas:
As overview information for students on the topic of "vibrations and waves". Important basis for understanding sound waves in acoustics.

Medientypen

Bild

Lernalter

11-18

Schlüsselwörter

Chart Optics Sound Wave (physics)

Sprachen

Englisch

Dieses Material ist Teil einer Sammlung

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Siemens Stiftung

The Ear, Hearing and Hearing Impairment: Speech as highly complex sound signal

Graphic:
Oscillographic curve of the spoken sentence "It's raining cats and dogs".

Speech sounds are fluctuating sound signals where the composition of frequencies changes all the time.
Aperiodical overlap periodical parts. Unlike noises, some of which have similar frequency curves, sound in speech is always the carrier of meaning or of messages sent out by the speaker. Other noises like smacking of lips, hissing, rhythms, basic pitch are typical of the individual (acoustic fingerprint) but not essential for the speech content!

Information and ideas:
Supplementary to worksheets and transparencies.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves
Communication and understanding

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Siemens Stiftung

Sound field and sound absorption

Schematic diagram:
Concentric propagation of sound waves. The lines of the same loudness are shown which decreases as the distance to the sound source increases.

Why do we hear less the further away we are from the source of sound?
Sound propagates from its source in a circular way, the sound energy spreads over an increasingly large area and the sound pressure decreases accordingly.
In a free sound field it decreases by about 6 dB every time the distance to source is doubled. Within a room, however, this only applies very close to the sound source.

Information and ideas:
Useful for discussing why we hear less the further away the sound source is.

Relevant for teaching:
Sound/acoustics: parameters
Vibrations and waves
Communication and understanding

Medientypen

Bild

Lernalter

11-18

Schlüsselwörter

Chart Sound Wave (physics)

Sprachen

Englisch

Dieses Material ist Teil einer Sammlung

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Siemens Stiftung

Speech recognition sentence - syllable - phoneme

Chart:
The components of speech, from phoneme to sentence presented visually.

The graphic shows the oscilloscope curve of the spoken sentence "It?s raining cats and dogs" and excerpts from the units from which speech is composed: sentence, word, phoneme.

Information and ideas:
Speech recognition and speech synthesis are very topical themes in the field of information and communication technology.
Further information on this graphic is available as information sheet on the media portal of the Siemens Stiftung.

Relevant for teaching:
The human body
Structure and function of a sense organ
Reception of impulses and information transmission
Sensory perception

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Siemens Stiftung

Perforation of the eardrum

Labeled graphic:
Simplified illustration of a perforated eardrum.

A perforated eardrum can occur when foreign bodies, for example, instruments to clean the ears, are stuck in too far or when there are loud bangs near the ear.
Violent blows to the ear can also cause perforation.

Minor tears or perforations can heal up by themselves provided they get the proper treatment. In any case, a doctor should always be consulted!

Information and ideas:
Can be used for illustration purposes on the subject of "Ear diseases" either on transparencies or worksheets. Supposedly "harmless" minor problems can turn into serious damage to the ear.

Relevant for teaching:
Hearing defect/hearing impairment