From the developer: "The Home Audiometer Hearing Test software turns your PC into a machine you can use to test your hearing through a standard sound card. While this is clearly not as accurate as a professional audiometer, it can give a good indication if there is a hearing problem or not and how severe it might be. The accuracy is 10-15 dB compared to 5dB of a professional unit, over a total hearing range of 70dB. Features include: Test procedure to ISO standards; graphical display of results; system is calibrated by ear without external hardware; data analysis and categorisation. Registered users are eligible to unlimited updates when they are released."