If you have a sound system with bass and treble or tone controls, or a sound editing program, you can experiment with strengthening and weakening the high harmonics using the treble or bass tone control. Some filtered voice sound examples are here. A breathy voice has a spectrum with a strongly negative slope. This voice is produced when the vocal fold motion is not broad enough to close the glottis completely during the vibration cycle. Conversely, in loud speech or singing, which have a rapid closure of the vocal folds and a short open phase of the glottis Childers and Lee, ; Gauffin and Sundberg, , Novak and Vokral, , the spectral envelope is flatter the higher harmonics are less weak, the spectral tilt is less.
This flatter spectrum has relatively more power in the frequency range 1—4 kHz, to which the ear is most sensitive. It is possible to make high-speed video images of the vocal folds using an optical device endoscope inserted in either the mouth or nose Baken and Orlikoff, ; Svec and Schutte, Electroglottography Childers and Krishnamurthy, , which is described above, is less invasive but less direct and gives less information.
Although the flow through the glottis cannot be measured, it can be estimated from the flow from the mouth and nose, which can be measured using a face mask Rothenberg, or from the sound radiated from the mouth. Both techniques require inverse filtering Miller , which in turn requires knowledge of, or assumptions about, the acoustic effects of the vocal tract and sometimes assumptions about the features of the waveform of the vocal flow one is aiming to measure.
As discussed above, acoustic resonances in the vocal tract can produce peaks in the spectral envelope of the output sound. In acoustics, it usually means the peak in the spectral envelope, which is the meaning on this site.
We discuss the different uses in more detail on What is a formant? In non-tonal languages such as English, vowels are perceived largely according to the formant frequencies F1 and F2 in the sound Peterson and Barney; , Nearey, ; Carlson et al.
F3 has a smaller role in vowel identification. F4 and F5 affect the timbre of the voice, but have little effect on which vowel we identify on hearing it Sundberg, We repeat below the plots of F2,F1 for two accents of English. Note that, in these graphs, the axes do not point in the traditional Cartesian direction: instead, the origin is beyond the top right corner. This choice maintains that tradition approximately. These maps were obtained in a web experiment: listeners judged what vowel had been produced in synthetic words in which F1, F2 and F3 were varied, as well as the vowel length and the pitch of the voice Ghonim et al.
We repeat the figure showing the vowel planes for US and Australian English measured in an on-line survey Ghonim et al. To understand how the resonances work in the voice, we can picture the vocal tract from the glottis to the mouth as a tube or acoustical waveguide.
It has approximately constant length, typically 0. However, the cross section along the length can be varied by moving of the tongue, mouth etc. The frequencies of the resonances depend upon the shape. The frequencies of the first, second and i th resonances are called R1, R2,.. See this link for a discussion of the terminology. When pronouncing vowels, R1 takes values typically between Hz small mouth opening to Hz.
Increasing the mouth opening gives a large proportional increase in R1. Opening the mouth also affects R2, but this resonance is more strongly affected by the place at which the tongue most constricts the tract. Typical values of R2 for speech are from about to Hz. The resonant frequencies can also be changed by rounding and spreading the lips or by raising or lowering the larynx Sundberg, ; Fant, Similarly, reducing or enlarging the cross section near a pressure node respectively lowers or raises the resonance frequency.
Conversely, reducing or enlarging the cross section near a pressure anti-node respectively raises or lowers the resonance frequency. This explains some features of the tongue constriction. The nasal tract has its own resonances, and the nasal nose and buccal mouth tracts together have different resonances.
The lowering the velum or soft palate couples the two, which affects the spectral envelope of the output sound Feng and Castelli, ; Chen, Understanding why takes a bit of work.
See Standing Waves for the basic physics and Pipes and harmonics for example resonances. Nasal vowels or consonants are produced by lowering the velum or soft palate, see Figure 1. The nasal tract also exhibits resonances. Coupling the nasal to the oral cavity not only modifies the frequency and amplitude of the oral resonances, but also adds further resonances.
The interaction can produce minima or antiformants or 'holes' in the spectrum of the output sound Feng and Castelli, ; Chen, Some comments about frequency and hearing are appropriate here. The voice pitch we perceive depends largely on the spacing between adjacent harmonics, especially those harmonics with frequencies of several hundred Hz Goldstein, For periodic voiced speech, the harmonic spacing equals the fundamental frequency of the fold vibration.
However, the presence of a fundamental is generally not needed for pitch recognition in speech or music : pitch comes essentially from the harmonic spacing or the period of repetition in the pressure signal; the two are equivalent. Experiment : record a musical phrase, preferably fairly low, with at least some notes below middle C.
Then filter it with a strong high pass filter or filter several times so as to remove the fundamental. Of course it will be much less bassy, but can you still recognise the correct pitch?
Except for high voices, the fundamental in speech usually falls below any of the resonances, and so may be weaker than one of the other harmonics. However, its presence is not needed to convey either phonemic information or prosody in speech. Prosody refers to the rhythm and the pitch pattern: prosody is the 'melody' of speech. Experiment : record a sentence. Listen to it and estimate the pitch range.
The look at its spectrogram and observe the range of fundamental frequencies. The pass band of hard-wire telephones is typically about to Hz, so the fundamental is usually absent or much attenuated. The loss of information carried by frequencies above Hz e. Their fundamental frequencies are not carried by the telephone line.
Can you hear their pitch? Of course, they are less 'bassy' than if you heard them live, but is the pitch any different? Then see the remark about pitch in the preceding paragraph. Our hearing is most sensitive for frequencies from to Hz. Consequently, the fundamentals of low voices, especially low men's voices, contribute little to their loudness, which depends more on the power carried by harmonics that fall near resonances and especially those that fall in the range of high aural sensitivity.
Another Experiments : i make spectrograms of your own voice. Varying the spectral envelope of the voice is part of the training for many singers. They may wish to enhance the energy in some frequency ranges, either to produce a desired sound, to produce a high sound level without a high energy input, or to produce different qualities of voice for different effects. Characteristic spectral peaks or tract resonances have been studied in different singing styles and techniques Stone et al.
In this laboratory, we have been especially interested in three techniques: resonance tuning , harmonic singing and the singers formant. Vocal tract resonances Ri give rise to peaks in the output spectrum Fi. However, the relation between Ri and Fi is a little subtle. This is illustrated in the cartoons here and below. This section follows Wolfe et al, Below, it is modelled as a simple cylindrical pipe to explain, only qualitatively, the origin of the first two resonances. The dashed line in the graph is for a cylinder.
See this link. This graph of impedance at the glottis as a function of frequency is taken from Wolfe et al Below it is a gain or transfer function : in this case the ratio of presure at the lips to that at the glottis. Usually we think of the frequency as being that of the fundamental, but it can be useful to discuss the behaviour of harmonics, too. At this stage, it is helpful to introduce the acoustic impedance , Z , which is the ratio of sound pressure p to the oscillating component of the flow, U at a particular location, usually the entry or exit of a duct.
This link gives an introduction to acoustic impedance. Z is large if a large variation in pressure is required to move air, and conversely. So Z is large at the glottis at frequencies for which large acoustic pressures produces only a small acoustic flow.
However, at these frequencies, Z is small at the mouth, where low acoustic pressure drives a relatively large acoustic air flow out of the mouth. Z is a complex quantity, meaning that p and U are, in general, not in phase, so that Z has both a magnitude shown in the plots at right and a phase. The in-phase component the real component when complex notation is used represents conversion of sound energy into heat or sound radiation.
When the p and U are in phase, the impedance is resistive and the input energy in each cycle is lost, usually by radiation as sound and typically to a greater extent by viscous and thermal losses between the wave and the duct.
A small mass of moving air in a sound wave stores kinetic energy but, because of its inertia, pressure is required to accelerate it. Flow of air into a small confined space increases the pressure, storing potential energy in the 'springiness' of the air. When the dimensions of a duct are not negligible in comparison with the wavelength, p and U vary along its length.
Z often varies strongly with frequency and the phase changes sign at each resonance. The plot at right shows the calculated impedance at the glottis, which we might write as Z G. The resonances are not purely acoustic: because the surrounding tissues are not rigid, their mechanical properties are involved, especially at low frequencies Hanna et al.
A pressure p at the lips is required to accelerate a small mass of air just outside the mouth: its inertance is not zero, but is usually Z rad small. At high frequency, however, larger accelerations are required for any given amplitude acceleration is proportional to amplitude times frequency squared, see this link , so Z rad increases with frequency.
In a confined space inside the vocal tract , acoustic flow does not spread out, so impedances are usually rather higher than Z rad. As we explain in this link , Z in a pipe or in the vocal tract depends strongly on reflections that occur at open or closed ends.
A strong reflection occurs at the lips, going from generally high Z inside to low Z in the radiation field. Suppose that a pulse of high-pressure air is emitted from the glottis just when a high pressure burst pulse returns from a previous reflection: the pressures add and Z is high. Conversely, if a reflected pulse of suction cancels the input pressure excess, Z is small. This effect produces the large range of Z shown in the previous graph. These maxima correspond closely to the resonant modes of a closed-open pipe.
For the simple pipe, minima occur half way between the maxima: see the graph above. Caution: in this unrealistic example, the resonances are harmonically related. The solid line shows the new input impedance Z. The maxima in Z pressure antinodes or flow nodes are hardly changed. This makes sense: a local constriction of small volume at the input has little effect on a maximum in Z , where flow is small.
For modes where the flow is large, however, the air in the glottis must be accelerated by pressures acting on only a small area. So the frequencies of the minima in Z pressure node, flow antinode occur at lower frequencies. If the glottis is sufficiently small, Z f falls abruptly from each maximum to the next minimum, which thus occur at similar frequencies. So do the maxima in the transfer functions. This has the consequence for Z G that the range of inertive impedance approximately from minimum up to next maximum above is larger than the range of compliant impedance from maximum up to next minimum , so the acoustic load is expected to be more often inertive than compliant.
This is difficult to measure. The lungs have complicated geometry, with successively branching tubes, extending to quite small scale at the alveoli. This branching behaves acoustically a little like the expanding cross section in the bell of a brass instrument, and so gives reflections. For acoustic frequencies, it behaves very roughly like a tube open at the lung end and with an effective length of less than about 20 cm Ishizaka et al.
Its possible influence on the vocal folds is subtle and difficult to study. As we explained above, the resonances of the vocal tract occur at frequencies well above those of the fundamental frequency — at least for normal speech and low singing. Further, the frequencies of vocal fold vibration which gives the voice its pitch and those of the tract resonances which determine the timbre and, as we have seen, the phonemes are controlled in ways that are often nearly independent.
In most singing styles, the words and melody of a song are prescribed. Conversely, in speech, we have the subjective impression that we can vary the prosody independently of the phoneme — for example, one can usually replace a key word in a sentence without changing the prosody at all.
Each text message is limited to only characters at most, which, if exceeded, counts as two messages and is charged additionally. Text abbreviations solve this problem by cutting down some characters and giving room for more words. The tendency of using shorter form of words, phrases or sentences was carried away from text messages to social media communication apps.
Although those apps are free to use and have no character limit, text abbreviations still remain popular with them. They save time and make typing on small and inconvenient sensor keyboards more comfortable.
Aside from helping individuals, text abbreviations also help businesses in their SMS marketing campaigns. Every SMS costs money for businesses too, therefore, they can use abbreviations to save some money.
Even with the most in-depth research, one cannot find all text abbreviations in the world. They are countless and the number is growing every day. I was shocked. MHM, I think I could. As mentioned above, the list of English abbreviations increases day by day.
In contrast, shorthand pronunciations are like an initialism a set of initials in which you say the letters one-by-one for example, 'ESP' is an initialism for 'extra sensory perception' whereas 'esp. The online practice is to refer to shorthand, initialisms, or abbreviations as acronyms. The majority of the expressions you see above are not acronyms, but rather shorthand used while text messaging or IMing.
I know that as is we are in touch with how actual Japanese works but for learners it slows us down having to look up kanji combinations. Also many learning tools, even those aimed at native Japanese speakers, space words out a little bit to help students with their grammar and reading.
That would be a significant improvement to the Japanese lessons as well. May Jehovah continue to bless you richly. Mean while we get their info if interested and pass it along to someone who can actually speak the language and help them.
If you want something more complex go to school or buy a program that fits your needs and desires. Great app, as indicated above. The following data may be collected but it is not linked to your identity:. Privacy practices may vary, for example, based on the features you use or your age. Learn More.
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