Building Discrete R2R DAC Hat - Part 2

The distortion measured around 0.006%~0.009%, mainly 2nd harmonic, which is a good sign of good sounding DAC. The rest of harmonics are well controlled under -100dB range.
This DAC sounds hash when I first fire it up, but back to normal after many hours of burn-in time. It sounds very analog / natural.
I spent a few of months to choose best / suitable parts for this project, especially choosing suitable capacitors for its application, and more than 20++ versions of FPGA code.
Brief spec here:
Raspberry Pi Hat , using " R-Pi DAC" as driver in moode audio / volumio / Pcp / etc
Support 24 bit , 384Khz
Resistors on bit 14 to bit 24 hand-matched down to 0.005% , bit 8 to 14 matched down to 0.01% , and bit 1 to 8 = 0.05%
unbalanced RCA stereo output, at 2V RMS
Built-in I2S isolator
Nos ( Non over sampling )
RC analog filter
low noise regulators with LC filters
bit no. 21 to 24 are driven by FPGA internal thermometer counter with a bunch of matched resistors automatically paralleled into more precise resistors and also corrected glitches -24dB lower than normal R2R DACs.
EDIT 2023 ** I constantly build this in small batch. Currently V1.85 Please contact me if you are interested :) **
You can find my email in here: / audiophilediyer
or browse my web page audiophilediyer.com
C.G.Ew
audiophilediyer.com