20 bit A-to-D & D-to-A converting systems for digital audio

Analog-to-digital (A-to-D) and digital-to-analog (D-to-A) conversion systems with 20-bit resolution are described. The A-to-D conversion system has two 16-bit A-to-D converters, and the system matches them completely digitally. The D-to-A conversion system consists of a digital filter, a noise shaper, and an 18-bit D-to-A converter. Both systems use existing devices, therefore their resolution can be improved with the advance of device technology. The A-to-D system has a 120-dB signal-to-noise ratio, an important factor for audio equipment.<
>