The AEROPHONE makes accurate documentation of vocal function easy. It can provide either records for research and ongoing treatment or instant bio-feedback to the patient. The AEROPHONE comes with two flowheads, one for peakflow and vital capacity measurements, and one for measurement of airflow during phonation. The AEROPHONE is extremely quick and easy to set up. The software and control functions operate on a standard PC with sound board and all results are displayed in clearly visible formats on the monitor screen, in speadsheet and on printouts. Windows operating systems are used (Win98, WinME, Win2000, WinXP and Vista.) Wide range of functions: The AEROPHONE provides calibrated recordings of: • Sound pressure level, • Air pressure, and • Airflow. Based on these recordings the instrument computes 32 valuable parameters describing the voice function and the respiratory function. The most important parameters are shown in color XT plots, XY plots or as regression lines. Facility for registration of Voice Range Profiles (Phonetogrammes) of song with belonging airflow registration is presented in colors.