FDA-1 PCM1794A DAC new FFT measurement for full balance mode

After some time, it is time to disclose the FFT measurement of this wonderful DAC by AP SYS-2522.  To achieve this good measurement results, the following changes are made:

  1. L5 is removed for both pcb
  2. C51 change to 560uF
  3. Add two ground wires 1 and 2 (RED) as shown in connection diagram
  4. Use separate 9Vac windings for each pcb from R26-10 r-core transformer
  5. OCL mode is used

All input signal are throught SPDIF @ 0.5Vpp FS=44.1k 24bit data.

FDA-1 FB connection diagram

FFT FDA-1 FB measurement results

Update Dec 7th 2010: Add new FFT measurement below for distortion and frequency response at -1dbFS, -10dbFS, -20dbFS, -40dbFS and -60dbFS.  Output load at 600 ohm.

FDA-1 FFT 600 load FR and Dist

Comments are closed.