From The Moscow State Academy of instrument Making and Computer science:
The audio frequency sinusoidal signal generator. Works with 16 and 24 bit sound cards with sampling rate up to 384 kHz. Independent channels frequency and amplitude controls. Adjustable phase shift between channels. A step of frequency setting is 0.0001 %; a level - 0.1 dB; phases - 0.1 degree. A real time signal synthesis. The minimum coefficient nonlinear and intermodulation distortion is limited only to quality of a used sound card.