The Accuphase DC-901 showcases mastery of sophisticated digital technology and creative circuit topology. It is a digital processor designed to bring out everything the SA-CD format has to offer. A new technique called MDSD allows straight D/A conversion of the DSD signal. Multiple DSD signals delayed through digital processing in an ultra-high-speed FPGA are converted by separate D/A converters. After D/A conversion, summation of the multiple data is performed, resulting in an ingenious moving-average filter circuit with double-speed accuracy.
An important characteristic of MDSD is the use of MDS type D/A converters which keeps conversion errors to an absolute minimum. At the same time, the MDSD circuit acts as a high-cut filter with completely linear phase characteristics. The end result is a digital signal of outstanding quality, allowing the music to emerge in perfect clarity, demonstrating the ultimate potential of the SACD format.
- Ultra-high-speed FPGA harnesses digital processing power to implement innovative MDSD reproduction with double-speed high-precision moving-average filter circuit
- Sixteen MDS type D/A converters driven in parallel. Each channel uses two Hyperstream™ DAC chips (ES9018) in parallel
- “Direct Balanced Filter” performs totally separate analog low-pass filtering for line and balanced signal paths
- “Direct Balanced Filter” provides totally separate analog low-pass filtering for balanced and unbalanced signal paths
- D/A converter printed circuit boards made from glass fluorocarbon resin with low dielectric constant and low loss
- EXTERNAL DSP input/output connectors (HS-LINK and optical) allow insertion of DG-48 in signal path
- Seven digital inputs: HS-LINK, balanced, coaxial (2), optical (2), USB
- Coaxial and optical digital outputs
- Line and balanced analog outputs. Phase selector switch for balanced output.
- Completely separate construction of digital and analog sections, each powered by a dedicated high-efficiency toroidal transformer