Test Methodology:
In this test we exclusively test the frequency response of the ADC by not including the the DAC in the measurements. We do this ny measuring the ADC output from an S/PDIF serial stream generated by the Preamp which we then feed directly into the digital input of the dScope. Since the Preamp samples at 192kHz by default. the Toslink output of the Preamp will not handle anything above 96kHz so we have to use the Coax out for this test. NB it is possible to switch the preamp into sampling at 48 or 96 kHz but by default the Preamp is shipped at its highest sampling rate so we use this for the test.
dScope Analog Output -> UP Analog Input
UP S/PDIF or Toslink output -> dScope S/PDIF or Tosiink Input
Conclusions:
Only 0.3dB down at 20Hz !!
