E-Course on voice range profiling and speech range profiling, including the software ‘Vox Phonetography’.
Whenever it suits you! This e-learning contains mainly videos but also other documents, that you can view and use for one full year.
Certified SLPs with a specialization in voice disorders.
€770 €530 when you as an early bird

This Vox Phonetography e-course is an essential course for SLPs who work with voice and want to use voice and speech range profiling in their daily work.

Phonetography provides an objective, visual representation of voice capacities in pitch (f0) and loudness (IL). A phonetogram is of interest as a diagnostic and evaluative tool in the treatment of voice disorders. You can use it to determine the limits of vocal performance, measure the degree of voice disturbance and evaluate voice therapy on a functional level. You can also objectively measure the habitual speaking voice and the use of voice by means of the speech range profile. Vox Phonetography is a modern, cheap and science-based phonetography program. In this course you will learn to work with Vox as a modern medium for making phonetograms. One Vox license is included in the course.

In this course, taking around six hours of video material spanning over three weeks, you will get a complete theoretical and practical understanding of phonetography. It’s unique as the only e-course on this topic, but also because of the blend of theory, practice, and demonstration of the software. You refresh the anatomy and physiology of voicing, you learn the purpose and recording protocol of the voice and speech range profiles and you understand the clinical value of phonetographic measurements. You make and interpret phonetograms yourself and you can do an optional assessment in the form of a case analysis to receive a certificate of completion. The emphasis in the course is on disorders of the speaking voice, not the singing voice.

Become an expert in voice- and speech range profiling and register today.

Course content

Module 1: Theoretical understanding

(Video) The sound chain – part 1 – recording conditions, microphone and hardware
(Video) From sound to phonetogram – part 1 – fundamental frequency and intensity level 
(Video) Relevance – the broader voice diagnostic context
(Document) Slides – presentation slides

Module 2: Using Vox, configuration and calibration

(3 Videos) Using Vox – installation, configuration, menu navigation, settings and recording
(2 Videos) Calibration – theory and practice, demonstration

Module 3: Speech range profile

(2 Videos) The speech range profile – theory, practice and interpretation, demonstration
(Document) The speech range profile interpretation chart – including norms/reference data for the clinically important variables
(Document) Slides – presentation slides

Module 4: Theoretical understanding

(Video) The sound chain – part 2 – signal to noise ratio, frequency weighting
(Video) From sound to phonetogram – part 2 – the z-axis and voice quality measurements 
(Video) Accuracy and intersystem reliability – explaining the high accuracy of Vox with two studies
(Document) Slides – presentation slides

Module 5: Voice range profile

(2 Videos) The voice range profile – theory, practice and interpretation, demonstration
(Document) The voice range profile interpretation chart – including norms/reference data for the clinically important variables
(Document) Slides – presentation slides

Module 6: Assessment (optional)

It is possible to do an optional case study after completing all previous modules. In this case study, you will apply all of your theoretical and practical knowledge of phonetography and record, interpret and analyze a complete phonetogram. Your phonetogram and interpretation mark the end your course. After the instructor views your progress and assessment, you receive a certificate of completion.

Extra module

(Video) Beyond diagnostics – using Vox during voice therapy
(Video) Advanced Vox functions – demonstration



Contact information


Time investment

The first three modules will be available after purchase. After 7 days you gain access to the modules 4 and 5, after 14 days you gain access to module 6 and the extra module. In total, you have 365 days to complete the e-course.
We estimate that you need approximately 1 hour to complete each module. Excluding the extra module and including your assessment, that would mean around 6 hours in total. Your self study can amount to approximately 2 hours for all practical work, excluding any practice and use of the software itself.

Summarizing: after purchase you would use around 2 to 3 hours a week for the course and practice in between. After the third week your course could be completed.

Practical information

Within 24 hours after registration:
– You receive an email with your invoice and a downloadlink for downloading your copy of the Vox Phonetography program;
– You receive an email with your log in credentials for your access to the e-course.


To learn about the theory behind phonetography, and directly apply it in practice.

The complete list of goals:

  1. The course participant understands the theoretical underpinnings of phonetography; 
  2. The course participant has sufficient knowledge with regards to acoustics, materials/hardware-, the sound chain and sound recording quality to make valid and reliable phonetography possible;
  3. The course participant knows and describes the physiological basis of vocal fundamental frequency and vocal intensity level;
  4. The course participant understands the significance of intensity level calibration and is competent in calibrating their own recording setup;
  5. The course participant is able to record a complete phonetogram in Vox Phonetography, both speech- and voice range profiles;
  6. The course participant knows and describes the diagnostic and evaluative value of phonetography in the broader context of care for people with dysphonia;
  7. The course participant interprets and compares phonetograms quantitatively (to norms and references) and qualitatively (in the context of pathophysiology, voice complaint, treatment choices and treatment evaluation).


Marthè Nijkamp, SLP and developer of Vox Phonetography.

Previous evaluations

“Marthè is a very passionate instructor instructor, I am very satisfied with the software”
– A. S., SLP

“The whole course is broken up into modules, which makes it easy to follow and understand”
– V. v. H., SLP

“At our outpatient clinic we have worked with several phonetographs, right now we are only using Vox because it is so simple and straightforward to use. I cannot believe that Vox only costs a tenth of the other phonetograph”
– S. S., SLP

“Easily the best course of the year”
– S. C., SLP

“Thanks to Vox I can confidently make VRPs in my private practice, they provide a lot of information and singers are always happy to take a copy home with them!”
– Anonymous

Only now:

1 Full Year Access to All Modules + Assessment + All Relevant Documents

to the value of €423


1 Vox Phonetography License

to the value of €347

Only for early birds:


Financial – Marthè Nijkamp owns Nijkamp Voice and Speech Pathology (Heerlen, Netherlands) and receives royalty payments from the sale of the Vox Phonetography voice analysis product.
Course Content Disclosure – This course focuses solely on Praat software and the Vox Phonetography plugins for acoustic voice analyses of voice signals, and will not include information on other similar or related products that might be used for the same analyses.