-Rega Dac Digital To Analogue Converter (Short case old version)

The Rega DAC is a 24-bit 32 to 192K digital to analogue converter incorporating an enhanced version of the Saturn digital to analogue converter circuit using a pair of Wolfson WM8742 DAC IC's with 5 user selectable digital filters. It has two isolated Co-axial, and two Toslink SPDIF 24bit 192K inputs and an isolated 32/44.1/48K 16bit USB input for use with personal a computer. The USB input incorporates a PLL based clock for low jitter signal recovery. There is an isolated Co-axial and Toslink digital output, which mirrors any of the selected inputs. The digital output data has passed through the receiver PLL and thus has been re-clocked and cleaned-up. The input stage comprises of a Wolfson WM8805 digital receiver with a high stability low jitter reference clock driving the receiver PLL, Rega have used the same oscillator as used in the Isis CD players. The receiver, PLL and oscillator have their own dedicated power supplies. The DAC stage comprises of pair of parallel-connected Wolfson WM8742 DAC's, which is driven via a buffer stage, which ensures the integrity of the data being fed to the DAC IC's - this is a similar arrangement to that used in the Isis.

The output amplifier employs a discrete differential multiple feedback filer and output amplifier, with a higher cut-off frequency for the higher sample rates. Rega have decided not to use a sample rate converter and process the data at the incoming data rate as this keeps the signal processing to a minimum. All the capacitors associated with the analogue signal path are bypassed with polyester capacitors, and low impedance conductive polymer capacitors are used for DAC decoupling. The power supply utilizes a toroidal transformer, fast rectifier diodes and high audio grade capacitors. There is a completely separate power supply for the control microcontroller, which is separate to the digital & analogue audio stages. Special attention being paid to the inter IC control signals keeping the control data noise to a minimum.

Wolfson WM8742 DAC IC's with 5 user selectable digital filters

24-bit 32 to 192K digital to analogue converter

2 x isolated Co-axial and two Toslink SPDIF 24bit 192K inputs

32/44.1/48K 16bit USB input for use with personal a computer