The dCS 904 is a reference quality analogue to digital converter offering full 24 bit capability in all the standard sample rates from 32kS/s to 192kS/s. Sony DSD compatibility is also provided . The dCS 904 employs a hardware platform based heavily on FPGAs which facilitates easy model upgrades and performance enhancements. dCS's A/D converters use a patented multi-bit oversampling architecture that achieves indescribably low Differential Non Linearity. Consequently, the sound quality has a naturalness and transparency previously only associated with the best analogue tape recordings. Gain ranging is not used.