• What is voice?
• Can one’s voice be changed or is it God (or Nature) given and cant be changed?
• Are you aware of dimensions of voice?
• How is voice produced?
• What factors determine voice quality?
• What is fundamental frequency or pitch of voice?
• What is optimum pitch? 
• What is abuse of voice?
• What are the factors affecting voice?
• What is voice care or voice hygiene?
• What are the tips to be followed by a professional who uses voice extensively?

What is Voice? Each person’s voice is unique. Voice is an image arising in the mind of a listener on hearing a person’s speech or singing (sound or acoustic signal). Voice is the ‘sound-to-image’ mapping of a person. Some believe that voice reflects a person's personality. A ‘good voice’ reflects speaker's confidence. It makes a positive impression on the listener. A vibrant voice can make atmosphere lively. Of course, one could say if the voice is confident or depressed or cheerful etc. Looks of a person is determined by face (static), posture (quasi-static), and gestures (dynamic – example: facial expressions, walking style). Similarly, there are some static and dynamic factors associated with voice. Can voice quality be changed? The looks of a person can be changed by    Apparel    Make-up    Plastic surgery Similarly, Voice quality can be changed by    Voice culture (proper speaking habits)    Voice therapy (proper vocal exercises) and in extreme cases by    Phono-surgery (Botax injection to laryngeal muscles, surgery of larynx) Dimensions or Attributes of voice An analogy to heart beats: There are three attributes to heart: Rate of heart beats, loudness of heart beats and sound quality associated with heart beats. If you listen to heart beats using a stethoscope, you hear rhythmic beats which you count as number of beats per minute. The number of beats per second is called frequency. One’s weight is expressed in kilos or pounds, height in inches or meters. Similarly the frequency is expressed in cycles per second or Hertz (denoted as Hz). Typical heart beats is 72 per minute or (72/60 = ) 1.2 cycles per second or 1.2 Hz. Also, you can hear the heart beats as strong or weak (loudness associated with the beats). Hear beats of different persons sound different. A doctor can distinguish such differences in the quality of sound associated with the beats irrespective of the rate of beats and loudness level may be the same. Voice has three broad attributes:     Fundamental Frequency (denoted as F0) or Pitch of a voice and expressed as Hz.    Loudness    Quality of voice Of the three attributes, fundamental frequency is a very important attribute which is widely studied.   How is voice produced? We explain the production of voice in lay man's terms with an analogy.  An analogy to clapping: When you clap, palms are brought together and apart cyclically. We hear a certain number of claps per minute. Rate of clapping can be fast or slow. Clapping can be soft or loud. There are different styles of clapping : merely patting fingers of one hand on the palm of another hand, regular clapping, keeping the palms cupped while clapping. Different styles of clapping gives rise to differences in the quality of sound.  In the voice box there are two muscles (vocal cords or vocal folds) which come together and collapse against one another and move apart. This happens cyclically. Air is slowly exhaled from lungs through the narrow gap (called glottis) between the vocal folds located in the voice box or larynx. The gap is only few milli-meters wide. Air flow is thus interrupted cyclically by these vibrating muscles. The interrupted pulses of air through the glottis (glottal pulses) travel through the mouth cavity and come out of lips as sound waves to produce audible sound. The shape of the moth cavity is determined by articulation. Speech production thus involves respiratory control, laryngeal control and articulatory control.  Voice is determined by an interplay of three factors:    Physiological: Respiratory, Laryngeal and Articulatory systems    Acoustic: Links the speaker and listener; F0, Intensity, resonances, intonation etc    Perceptual: Pitch, Loudness, voice quality, speaker's identity, emotion etc What is fundamental frequency of voice? The number of cycles of vibration (opening-closing) of vocal folds per second (not per minute) is the fundamental frequency associated with voice. Fundamental frequency is denoted by the symbol F0, read as "f-not". Sometime the word 'pitch' is used in place of F0. The average F0 value of a voice when uttering a long steady vowel is called the habitual F0 of the speaker. You can measure your habitual F0 using Vaghmi - Computerized Voice Therapy Software developed by VSS. Visual representation of voice An analogy: You are familiar with electro-cardiogram or ECG. This is a visual (or graphic) representation of the electrical activity of your heart. Electrodes pick up the electrical activity of the heart and an instrument produces a visual graphic representation.  When a person utters a steady long drawn vowel 'aaaaaa.....', the sound waves can be recorded using a microphone. An instrument or a computer with appropriate software can produce a visual representation of voice. The Figure below shows the graphic representation (called waveform) of sound waves of a vowel 'aa' for a duration of 1/10th of a second. We note that there are 15 cycles in 1/10th of a second, hence there will be 150 cycles in 1 second. We say that this voice has a F0 of 150 Hz.  Ex.: Listen to Steady Synthetic Vowel of F0=150 Hz   We describe a voice as bass voice (low pitch) or a shrill voice (high pitch). A typical male voice producing a steady vowel has a pitch of about 120 cycles per second or 120 Hz. F0 may be different for different male speakers producing a steady vowel 'aaa...' . It may lie within a wide range (80 to 160 Hz), but, 120 Hz is a typical value A typical female voice has F0 of about 220 Hz. A baby’s voice has a F0 of about 400 Hz. Ex.: Listen to Typical Male Voice of Low F0, Average F0 =150 Hz   Ex.: Listen to Typical Female Voice of High F0, Average F0=150 Hz   Ex.: Listen to Typical Child's Voice of Very High F0, Average F0=315 Hz   You can visualize your voice and hear your recorded voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. Steady Vs unsteady voice? A long sustained vowel is called 'phonation signal'. When a person utters a long duration sustained vowel, F0 is not exactly the same through out the vowel. Voice of a old person is unsteady. Voice of a depressed person is wavering.  For a normal person, there are small random variations in F0 that are not perceivable. The average F0 over a vowel is called the habitual F0 of the speaker. If these variations become large then we say the voice is "wavering" or unsteady. This is also referred to as tremor.  A large percentage variation is a cause for concern. Ex.: Listen to an Unsteady Voice with fluctuations in F0 A singer may produce intentional and musical variations. This will be a systematic variation. Ex.: Listen to a Female Singer's Voice with modulations in F0 You can measure variations in your voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. What is intonation? During speaking, speakers continually change F0 over vocalic regions of speech. When you say "How are you?", you are changing F0 through out the utterance. This change of F0 over an utterance is called intonation. The average F0 over test utterances is then spoken fundamental frequency. This is in contrast to habitual F0 associated with a phonation signal. Spoken fundamental frequency depends on the utterance, style of speaking, emphasis etc. Ex.: Listen to the utterance 'speech communication' with an intonation Ex.: Listen to the above utterance synthesized with constant F0 over voiced regions   You can visualize intonation in your voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. What is Optimum F0? What is abuse of voice? It is believed, by some voice specialists, that there is an optimum F0 for every speaker based on the anatomy of the voice box or larynx. Empirically the optimum F0 is determined as follows. First, find the lowest F0 that can be produced clearly by a speaker. Find key on a piano key-board that corresponds to this lowest F0. The optimum F0 will corresponds to 2 or 3 notes higher. If a speaker is not using optimum F0 then it is a factor causing abuse of voice. A singer can sing notes at different frequencies.  This means it is possible to change habitual F0 with practice to make it close to the optimum. A singer can use optimum F0 as the tonic note. You can measure Optimum F0 for your voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. You can practice control of F0 for your voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. What is loudness associated with voice? When you can hear and also understand what has been spoken by a speaker at a long distance, it is almost like speaker is shouting at the top of his/her voice.  This is an example of a loud voice. For some speakers, you have to strain to understand what is being spoken though you are standing at a close distance. This is an example of a soft voice. The strength of the voice depends on the force of impact of vocal folds in the voice box or larynx when they close for every cycle of vibration. Also, it depends on the articulatory habit which determines the characteristics of sound travel from larynx to lips.  If a speaker is speaking too loud or too soft, it is a factor of concern that may lead to abuse of voice. You can control loudness for your voice using Vaghmi - Computerized Voice Therapy Software developed by VSS. Loudness Vs Amplification? You can amplify a voice so that you can hear it from a distance. But, this is not same as a shouting voice.  We can still identify if the original voice was normal or soft. We say that the volume of sound has been increased by amplification. The volume of sound is measured in a unit called 'deci-Bell' or dB.  There are many extraneous factors that determine the sound volume like mouth to microphone distance, amplifier gain factor, sensitivity of the microphone etc. A soft voice with a greater amplification has the same sound volume as a loud voice with a lower amplification. In order to measure the sound volume accurately it is compared against a standard volume and the instrument has to be calibrated. Many instruments or computer programs only measure relative volume of sound. Study on loudness of a voice must include all factors such as breathing, voice production and articulation.   Quality of voice Just as the saying goes ‘ beauty lies in the eyes of the beholder’, listener’s choice of what is a good voice is subjective. This is similar to the taste one has for music. Hence there are no measurable units for quality of voice. Practicing voice professionals use some broad terms to describe the voices: Bright: Higher loudness without effort (not-shouting) Confident: Steady Pitch and Loudness level –opposite of wavering Melodious: Good correlation between Pitch and loudness Resonant: Articulation tuned to Pitch – Ringing Hoarse: Presence of noise component – absence of harmonics Pressed: Long closed phase in vibration cycle Breathy: Steep spectral slope, strong  fundamental Nasal: Heavily damped resonances     Factors to assess voice quality It is important to remember that voice quality depends not only on the functioning of the voice box or the larynx but also on articulation (enunciation or pronunciation), rate of speech (too rapid or too slow), intonation, pauses etc. Some of the factors are: Rate of speaking: Number of words per breath, Number of words per minute Rhythm of Speech: Accent and Inflections (Pitch range) Breathing Pattern: Speech as during fast walking Vs relaxed Pitch Level: Habitual F0 or Pitch  Loudness level: Deafening (too loud) Vs Whispering (too soft) Mood State: Sudden changes in pitch level, loudness and rhythm Clarity of Speech: Good articulatory habit Factors affecting voice quality Some important factors that affect voice quality are: Air Quality:  The most common air quality problem is dust; Dust from chalk, carpet, household dust, outside dust, dust from construction projects etc. Dust is an irritant to your airway, the wet or moist lining of our nose, throat, and vocal cords. When irritated, these air passages may become red and swollen, often causing a change in pitch and quality of your voice. Humidity: Too high or too low a humidity can be enemy to your natural voice. An ideal humidity for voice is about 40-50%. Noise:  Noise is considered the biggest air pollutant of all. The extra effort required to speak in noisy environments involves using more air for a louder voice, a higher pitch and greater precision in enunciation. This can severely tax our vocal equipment and prevent us from using our natural voice. Speaker-Listener Distance: Ideally speaker should use appropriate loudness level and not speak too loudly or softly. The loudness of our voice should continually adjust to the changing noise level around us, to the physical distance between us and our listener, and to the social circumstances. Hormonal changes: The dramatic voice changes in puberty experienced by both boys and girls, are evidence of impact of sex hormone on vocal tract and are normal. Puber-phonia is retaining pre-puberty pitch. Fatigue/stress: Voice is light, higher in pitch and lower in volume than usual. At these times it is not possible to have the kind of voice you would like to have. Stress causes us to make unusual demand on our vocal folds. Aging: Natural changes in Pitch. Allergies and infections: For people with sever airway allergies, the swollen and inflamed membranes of the throat and nose can produce hoarseness and even complete loss of voice. Fear: Pressed voice with higher Pitch, wavering, slower rate of speech. Hydration: A dry larynx (vocal tract) doesn’t function as well as moist one. Medication: Among over the counter drugs, the primary enemies of the vocal tract are aspirin and antihistamines. Continuous usage of aspirin can result in slight hemorrhaging of small blood vessels on the vocal cords, which will lower pitch and produce hoarseness. Recreational drug: Smoking is a primary enemy of developing a better voice. Voice care and hygiene Vocal hygiene in general means vocal health or even more simple avoiding activities or habits that troubles the vocal cords and overall affecting the voice of the individual. Suggestions for vocal health can be grouped into 3 major categories: 1.Vocal hygiene   2.Vocal rest   3.Vocal conservation Vocal abuse  Vocal abuse is excessive usage of laryngeal mechanism in various non-verbal abusive ways, such as continuous coughing, laughing, smoking. Such abusive behaviors can have negative effects on laryngeal functions and sometimes on vocal production as well. Some common ways one can abuse their voice: 1.      Yelling and screaming       2.Speaking against a background of loud noise 3.      Coughing and excessive throat cleaning 4.      Excessive talking or singing 5.       Excessive crying or laughing Vocal misuse  Vocal misuse may consist of excessive or inappropriate voicing, such as speaking at the wrong pitch. Excessive voicing such as screaming, yelling, enlarges the vocal folds. This vocal folds enlargement changes the sound of the voice.  Some common ways one can misuse their voice: 1.      Speaking with a hard glottal attack 2.      Singing excessively at the lower or upper end of their pitch 3.      Increasing the vocal loudness by squeezing out the voice at the level of the  larynx 4.      Cheer leading 5.      Speaking over a longtime at an inappropriate pitch level 5.      Speaking or singing for an excessively long period of time Professional voice care  Some tips for professional care of voice are:   Controlling the intensity of one’s voice and speaking at a softer levels can eliminate or reduce vocal strain 2.By taking a slightly larger breath than normal tidal breathing, increasing expiratory control can improve one’s breathing for various phonatory tasks 3.Reducing usage of voice can often do wonders for a tired voice. Reducing vocal usage maybe for just a few hours daily is sometimes helpful for overcoming vocal strain 4.Avoiding clenched-jaw pasture while watching, playing,reading etc., can promote greater vocal tract relaxation 5.Avoid talking or singing in the presence of a loud noise. 6.Avoid extremes of molar crunching (bruxism) 7.Stop smoking and avoid smoky atmosphere  Avoid working in a very dusty environment. Use masks in dust environment Reference  Daniel R Boone, PhD, Prof. Emeritus, Dept of Speech and Hearing, University of Arizona, Tucson, Arizona "Is Your Voice Telling On You? How to find and Use Your Natural Voice", Singular Publishing Group Inc., San Diego, California, 1991. Many of the important issues addressed by Dr Boone have been dealt within Vaghmi - Computerized Voice Therapy Software developed by VSS.     Go Back    |Home| Products | Vagmi Nada| Technical Support| Clientele | Expertise | Resume | Publications | Contact Us |

Copyright 2002 Voice and Speech Systems