By popular demand, here I am making publicly available a little utility I developed and find useful in my audio work. It operates at sample rates from 44,100 to 768,000 samples per second. It generates sine wave signals of the highest precision, in the full range of 10 Hz to half the sample rate (Nyquist limit), at attenuation values from 0 to 90 dB, generate pink and white noise, and linear and logarithmic sweeps. It will only work with sound cards that have an ASIO driver. (Don't have ASIO but still need a signal generator? Then try the Audio Test File Generator. It will only work with Windows (but also seems to work fine under Ubuntu Linux w/Wine & Jack). It will work with sound card at 16, 24, or 32 bits (some 20 bit cards may also work) and 32 bit float. The application generates a little debug file that provides information about the sound card and error reports. The complete specifications are available here. Since version 2.11 the selectable musical notes are calculated to a precision rounded up to 11 decimal places, becoming a precise standard reference for the modern Even Tempered Scale to which you can calibrate your equipment and musical instruments.
Check out ASIOExtender
ASIOExtender™ gives you the ability to use the professional ASIO audio protocol that both your music player and DAC support, along with the versatility of VST3 plugins in your personal audio setup to apply post processing to the audio before it is rendered.