Voice Control Module
Related Modules: The following related modules may also be of help to the client:
Breath Support
Intonation and Accent
A Note on Scoring: In the following taks, the score is computed as follows. The duration for which a task is being performed is recorded. Let us call this 'Total_Duration'. The duration for which a task has been completed successfully is also recorded. Let us call this Success_Duration. Then,
Score in per cent = 100 (Success_Duration/Total_Duration).
A Note on Calibration: The voice level (goal) to be achieved can be set in dB. The signal level that is recorded in a computer depends on several factors: microphone sensitivity, mic to speaker distance, internal software gain settings etc. Hence for dB reading of the measured intensity to be meaningful, calibration is required.
In the 'Settings' menu, there is an option to calibrate the measured intensity in dB-SPL.
Measurement of Optimum Pitch
Pitch Meter menu option can be used to measure the habitual pitch and to estimate the optimum pitch.
A horizontal bar graduated to read pitch is shown. There are three options for the range of pitch scale corresponding to male, female and child voices. The measured pitch of client's voice is shown by the location of a vertical line on the horizontal graduated bar. Also the value of the measured pitch is shown.
The client is asked to say a steady vowel at his/her usual pitch. The value of the pitch shown corresponds to the habitual pitch.
The client is then asked to say a steady vowel at the lowest possible pitch, yet with a distinct quality. This pitch is identified on a piano keyboard. The pitch, three or four keys above this lowest value, is referred to as the optimum pitch. It is empirically established that speaking with the optimum pitch will enable the person to speak for a longer duration without the voice getting tired.
Alternately, the appropriate pitch based on the gender and age of the speaker can be deduced from a Normative Table.
Therapy Practice
- Volume or Intensity Control
There are 4 sub-menu options in Volume or Intensity Control:
- Mowgli reaches bananas
This menu option is for a client with a soft voice that is hardly audible.
The voice level has to be maintained above that set for the goal (in dB).
Here the size of Mowgli increases with the increasing voice level and vice-versa.
The task is to speak at a level greater than the value set for the goal so as to help Mowgli reach the banana.
If voice is soft, a feedback message 'Louder' is shown. If goal is achieved, a reinforcement message 'Good' is shown.
- Rainbow
This menu option is for a client with a soft voice that is hardly audible.
The voice level has to be maintained above that set for the goal (in dB).
More and more colours of a rainbow appear with the increase of voice level.
The task is to speak at a level greater than the value set for the goal so as to complete the rainbow.
If voice is soft, a feedback message 'Louder' is shown. If goal is achieved, a reinforcement message 'Good' is shown.
- Fish in a jar of water
This menu option is for a client with a very loud voice.
The voice level has to be maintained below that set for the goal (in dB).
Fish are swimming in a jar of water and a fish will jump out of water with the increase of voice level.
The task is to speak at a level lower than the value set for the goal so as to keep fish floating in the jar of water.
If voice is loud, a feedback message 'Softer' is shown. If goal is achieved, a reinforcement message 'Good' is shown.
- Prism
This menu option is for a client with a wavering or unsteady voice level or volume.
Also, this menu option helps to achieve a fine degree of control over voice level (i.e., to keep the voice level steady at a desired level).
The voice level to be maintained is set as the goal (in dB). Also, the tolerance limit is set.
A ray of light passes through a slit and strikes a prism and a spectrum of colours is seen on the other side.
The angle of the ray of light increases when the voice level increases and vice-versa.
The task here is to maintain the voice level steady, neither too high nor too low, such that the spectrum of colours is seen steadily.
- Pitch Control
There are 3 sub-menu options under Pitch Control.
- Pitch Meter
Once the optimum pitch or the appropriate pitch to be used is determined, Pitch Meter menu option can be used to practice saying a vowel or singing a note at the desired pitch.
The desired pitch to be achieved is ‘set as the goal’. Tolerance limit can also be set.
A Green patch centered at the goal appears in a graduated bar. The width of the green patch is wider for ‘easy’ level and narrower for ‘difficult’ level.
A tone may be played at a value of pitch corresponding to the goal. Tone is to be heard over headphones. This may be required during the initial phase of the practice.
The client has to say a steady vowel whose pitch corresponds to that of the goal.
When the measured pitch of the client's voice is lower than the goal set, the vertical line corresponding to the achieved pitch is to the left of the Green patch and is shown in Yellow colour and a message 'Increase Pitch' appears. The score decreases.
When the measured pitch of the client's voice is higher than the goal set, the vertical line corresponding to the achieved pitch lies to the right of the Green patch and is shown in Red colour and a message 'Decrease Pitch' appears. The score decreases.
When the measured pitch of the client's voice is within the limits set, the vertical line lies within the Green patch and is shown in Green colour and a reinforcement message 'Good' appears and the score increases.
- Pitch Bird
The desired pitch to be achieved can be ‘set as the goal’. Tolerance limit can also be set.
A tone may be played at a value of pitch corresponding to the goal. Tone is to be heard over headphones. This may be required during the initial phase of the practice.
When the client says a steady vowel, a flying bird is seen. The task is to say a steady vowel at the desired pitch so that the bird sits on the perch as long as possible.
The bird’s position is to the left of the perch when the measured pitch of the client's voice is lower than the goal. A message 'Increase Pitch' appears. The score decreases.
The bird’s position is to the right of the perch when the measured pitch of the client's voice is higher than the goal. A message "Decrease Pitch' appears. The score decreases.
When the pitch of the client’s voice is within the tolerance limits around the goal, the bird sits steadily on the perch. A reinforcement message 'Good' appears. The score increases.
- Pitch Scaling
The above menu options are meant for steady vowels or steady nasals. In practice, one has to become aware of the voice to be used in day-to-day conversations. Assume that the habitual pitch is 160 Hz and the optimum (or the appropriate) pitch is 120 Hz. The pitch has to be lowered by a factor 0.75. This scale factor is set. Then the client speaks in his/her habitual pitch (close to 160 Hz). The program scales the pitch of the voice by the factor set (0.75) and plays back the utterances. This gives the client a perceptual impression (to serve as a model) as to how he/she should sound while speaking in normal day-to-day conversations.
- Simultaneous Control of Volume and Pitch
Usually, when one is asked to increase pitch the person may increase the level of the voice instead of the pitch and vice-versa. For a good control over voice, one must be able to control both volume and pitch independently. In this menu option client can practice saying a vowel with a steady pitch and varying volume or a steady volume and varying pitch or control both volume and pitch within certain limits.
A box appears setting the limits for the volume and pitch. When the client says a vowel, a dot is displayed whose position depends on the measured volume and pitch. If the client achieves the goal, the dot appears Green else it appears as Red. Using the position of the moving dot as a feedback, the client learns to control the voice and attempts to bring the dot to lie within the box. The score achieved is displayed.