Rega's flagship Reference CD player
Rega Isis is the Reference CD player with twin Burr-Brown PCM1794 DACs in dual-mono configuration, discrete Class A stages, balanced XLR output and galvanically isolated USB input.
Isis is Rega's reference CD player and combines proprietary disc-reading technology with a D/A conversion section developed to keep digital and analogue domains separated and controlled. Conversion uses two Burr-Brown PCM1794 DACs operating in parallel dual mono, followed by operational amplifiers of discrete Class A design and by optimised filters. The chassis is CNC machined from anodised aluminium and incorporates dedicated power supplies for the different sections.
Key features
- Operational amplifiers and filters of discrete Class A design
- Analogue section optimised for sound performance
- Audio-grade electrolytic capacitors
- Rega K-Power reservoir capacitors
- Wide dynamic range and low distortion
- Custom CNC-machined aluminium chassis
Dual-mono conversion
The analogue section uses two Burr-Brown PCM1794 converters working in parallel dual mono and driving a current-to-voltage conversion stage built in discrete Class A. From here the signal passes to a further output amplifier, again discrete Class A. Balanced operation is maintained all the way from the DACs to the analogue XLR outputs, while component choice and board layout are intended to reduce interaction between digital circuitry, analogue section, motor and control circuits.
Separate power supplies
The analogue section is fed by a 50 VA transformer of its own, providing galvanic isolation from the digital circuitry. The digital section also uses a dedicated 50 VA transformer; the motor, user-interface processor and display have separate supplies as well. The circuits employ Rega K-Power capacitors, fast diodes and numerous local regulators to maintain low supply impedance and reduce noise transfer between different areas of the player.
USB and disc handling
The USB input lets a computer use the internal DAC and employs an isolated dual-clock interface with its own regulated supply. Galvanic isolation limits ground currents and noise generated by the computer power supply. During initialisation Isis also analyses each disc and adapts CD-processor control to the characteristics of the medium, optimising reading and error correction even with less-than-perfect discs.
Supplied accessories
The Reference CNC remote control is included for operating the player.
