CICI DAC - another PCM2707+PCM1794A reincarnation

I came back to listen to my old PCM2707/1794A DAC which I built few years back, and I was amazed that I could not hear any difference in my now upgraded system (RMI-FC100, Dynaudio Focus 340, ZD5) between Denon DVD2900, Cambridge Audio StreamMagic CXN, Topping D50, and my old DAC. Moreover, I have yet to hear a difference between high res material and good ol' 16/44 recordings. So here we are again, another stab at immortal PCM2707/1794A reincarnation, simple and awesome (to me at least:).

I hate mixing SMD and through hole, so it's all SMD 1206, still manageable by old school guys like me. All power pins are cleared by TI LDO regulators and there is separate Microchip ClockWork clock pumping beats into PCM2707. No capacitors in signal path, thanks to TI voltage inverter.


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I friend of mine tested older version of this DAC against a commercial multibit, blah-blah DAC, which he paid 2399$ - he could not hear a single difference. He does hear a difference between DACs in his system easily. He asked me to incorporate toslink since he has all his music on CDs, so here we go again, back to drawing board. DIR9001 inserted in schematics and almost ready to go. Data lines will be switched with !AUDIO signal from DIR9001, with SN74LSV157 multiplexer.
One small correction needs to be done on pcb in order for automatic switching between usb and spdif to work. For some reason, AUDIO signal does not change regardless of spdif input signal, so ERROR needs to be used instead, so AUDIO PIN trace needs to be cut and ERROR connected to it instead.

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