Voice Range Profile, Model 4326

Introduction

The Voice Range Profile (VRP), also known as the phonetograph, is a technique for the examination of voice behavior. It has been a standard part of European phoniatrics and logopedics for many years. VRP plots a subject’s amplitude and fundamental frequency ranges in a two-dimensional graph (with the x-axis representing fundamental frequency and the y-axis representing amplitude). As a maximum performance test, VRP is a sensitive indicator of vocal function.  

The VRP plots SPL versus Fo to
 produce a "voice map" of the subject's 
ability to vocalize at various levels and
 frequencies.

Numerical results can be printed or saved as a file.

The Need for VRP

As revealed in the professional literature, the clinical efficacy of this technique has been studied extensively and a bibliography is available from Kay. In the Recommendations for Acquisition of Acoustic Voice Signals published by the National Center for Voice and Speech (1994), VRP analysis is recommended as part of acoustic phonatory assessment for pathological voice. VRP is unique in its ability to detect subtle changes in vocal function. Professional singers, who as “vocal gymnasts” often appear normal in other vocal function protocols, may find that the VRP reveals an altered voice range profile. The same is often true of other patients who complain that something feels wrong with their voices, but, at normal fundamental frequencies and levels, show no discernible abnormality.

A reference pattern, see outline above,
from a prior visit can be overlaid on
current analysis to highlight changes in VRP.

Why Kay’s Voice Range Profile is Unique

Although previous phonetograph instrumentation was dedicated and expensive, the Voice Range Profile option for the CSL4400, Model 4326, is relatively low in cost, using the standard CSL hardware with a boom-mounted microphone (for constant microphone-to-mouth distance). Frequency tones generated by the program are used to prompt the patient to vocalize the target fundamental frequency at all achievable amplitudes. CSL hardware includes the capability to automatically and precisely adjust input sensitivity based on signal strength; the VRP program utilizes this unique hardware feature. By tracking the signal’s level during input, while adjusting the signal attenuation in known increments, the VRP can accurately measure and display the extraordinary dynamic range of the human voice. Kay’s Voice Range Profile is far superior to software-only versions because of the excellent input (i.e., recording) robustness of CSL, Model 4400, hardware as compared to generic sound cards. First, CSL has very high signal-to-noise ratios. This is needed for accurately measuring low-level voicing. Second, CSL input is calibrated for the supplied microphone. And third, the unique ability of the CSL to adjust the input level in precisely calibrated increments over a 70dB range, coupled with the 96dB range of the A/D, provides well over 100dB of voice range plotting.  

Features

•  VRP is a sensitive indicator of vocal performance range and is an early indicator of potential vocal problems.

•  VRP is useful for benchmarking a patient’s voice throughout therapy and beyond.

•  VRP is uniquely capable of accurately displaying the impressive dynamic range of professional singers.

Easy to Use

The Voice Range Profile is a relatively lengthy protocol because the examiner must elicit from patients their full range of amplitudes for each fundamental frequency. Kay’s VRP makes this easy by providing ready audio prompts and automatically tracking the patient’s voicing at each tone. Alternatively, examiners can let the patient simply voice any pitch and amplitude as the software tracks the results. A template allows ready and quick comparisons with prior examinations. And because CSL automatically adjusts input level in calibrated steps, the user can focus on the patient rather than on the procedure.

A tone for prompting the client can be played at any time.
 The standard keyboard allows selection of tone.

Extensive Dynamic Range

It is relatively easy to extract voicing parameters from voices at normal pitch and amplitude levels. VRP excels at extracting pitch and amplitude from an extremely wide array of vocal behaviors encompassing the range of human voices.   

Hardware Recommendation

VRP requires the special and unique features of the CSL, Model 4300B, because of its calibrated input, its extended dynamic range, and its ability to control input levels automatically during voice acquisition.

Current CSL, Model 4500 and 4150, software and database options include:

• Analysis-Synthesis Laboratory (ASL), Model 5104

• Applied Speech Science for Dysarthrias, Model 5153

• Applied Speech Science for Voice & Resonance Disorders, Model 5156

• Auditory Feedback Tools, Model 3506

• Disordered Voice Database, Model 4337

• Games, Model 5167

• Motor Speech Profile, Model 5141

• Multi-Dimensional Voice Program, Model 5105

• Neuroscience for Human Communications, Model 5155

• Palatometer Database, Model 4333

• Phonetic & Perception Simulation Programs, Model 5151

• Phonetic Database, Model 4332

• Real-Time EGG Analysis, Model 5138

• Real-Time Pitch, Model 5121

• Real-Time Spectrogram, Model 5129

• Respiration, Phonation and Prosody Simulation, Model 5152

• Signal Enhancement Program, Model 5142

• Sona-Match, Model 5127

• Speech Articulation: Animation of Muscle Vectors, Model 5154

• Video Phonetics Program and Database, Model 5150

• Voice Range Profile, Model 4326