The Waveview System is a complete turnkey hardware/software solution allowing researchers and students to visualize the airflow pulses at the glottis during voiced speech and singing using a fast, easy, non-invasiveA non-invasive measurement is one that does not require the introduction of instruments into the body. mask and inverse-filteringIn signal processing, for a filter g, an inverse filter h is one such that the sequence of applying g then h to a signal results in the original signal. Software or electronic inverse filters are often used to compensate for the effect of unwanted environmental filtering of signals software. The system is accurate down to zero frequency, not susceptible to low-frequency noise, compact, and easily calibrated.

The system uses a handheld mask with a transducer, a data acquisition box with USB interface, and software which can be run on any Windows PC or laptop. Acquiring data is easy: Your test subject vocalizes into the mask, and data is recorded and immediately visualized onscreen by the software. The user then uses the efficient, intuitive controls in the software to quickly and easily apply an inverse-filtering technique to the oral airflow recording, leaving only the airflow waveform from the glottis.

Waveview can do much more, however. The Waveview System also permits low-frequency phase correction of an EGG or microphone signal waveform, computes and displays average airflow and sound pressure level (SPL)Sound pressure level is a logarithmic measure of the RMS sound pressure of a sound relative to a reference value, the threshold of hearing. It is measured in decibels (dB) calculated from airflow, calculates and displays two versions of the AC/DC ratio first proposed by Isshiki, provides simplified offset and amplitude calibration for airflow, and offers a convenient means for correcting the time alignment between inverse-filtered glottal waveforms and EGG traces.

• Compatibility with Windows XP/Vista/7/8/10
• Powered by USB or external power supply
• Data automatically saved in standard 2-channel .wav format
• Adjustable gains to accommodate very quiet speech as well as loud singing
• OroNasalRelating to the mouth and nose mask for minimal acoustic distortion
• Easy-to-use inverse filter interface
• Shows clearly the correlation between the features of an EGG waveform and the features of the glottal airflow pulse. Includes EGG time correction and low frequency phase correction.
• Lets the user control and trim the inverse filter settings, with automatic pre-set settings also available.
• Waveview shows clearly the relationships between time and frequency domain correlates of voice parameters such as vocal period, formant frequency and formant damping, making it an excellent instructional tool.

Glottal Enterprises has developed the Waveview and computer programs for inverse filtering CV-mask (airflow) or microphone (radiated pressure) waveforms during speech and singing. We have kept the user interface simple and intuitive, to make it useful for students as well as voice researchers.

Waveview can be purchased as a complete turnkey system, incuding a CV mask, transducer, A/D and preampifier electronics, airflow calibrator, and microphone, or as software to use with your own hardware that produces signals in a standard WAV-file format.

Waveview is designed as a convenient computer program for performing inverse-filtering of an oral airflow (CV mask) or radiated pressure (omni-directional microphone) waveform. In performing inverse-filtering, it can be used with WAV-encoded files recorded by any system for capturing airflow or audio waveforms. However, Waveview can do much more. The Waveview program also permits low-frequency phase correction of a microphone signal waveform, computes and displays average airflow and sound pressure level (SPL) calculated from airflow, calculates and displays two versions of the AC/DC ratio first proposed by Isshiki and provides simplified offset and amplitude calibration for airflow.