MEASUREMENTS

The Accuphase DG-68 is a complicated product, comprising an analog–digital converter (ADC), digital signal processing (DSP), and a digital–analog converter (DAC). It also has digital inputs and outputs that bypass the ADC and DAC stages. JVS used it as a complete analog–analog processor, so, in addition to examining the individual performance of the ADC, DSP, and DAC stages, I looked at its behavior as set by JVS.

I used my Audio Precision SYS2722 system (see the January 2008 “As We See It”) to perform the measurements, repeating some tests with the magazine’s more-recent APx555 system. While Accuphase specifies the coaxial S/PDIF input as accepting data sampled at rates up 192kHz, it wouldn’t lock at rates greater than 96kHz to the coaxial digital output of either Audio Precision system. The optical S/PDIF input accepted sample