DAC AD1862: Almost THT, I2S input, NOS, R-2R

You can use miro psu for +5V (you need two), but make sure you use big heatsink for xmos rail, it draws 500ma. And 8V on transformer, i wouldn't go lower for that drop.

As for opamp supply, it depends what kind of opamp you use. There is no universal rule for that. From what i see on the market, most discretes will have least distorsions at 15v, but it's neglible if you feed them 12v, so don't stress over it. Read specs of the one you want to utilize, and fashion the supply by it.
 
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You can use miro psu for +5V (you need two), but make sure you use big heatsink for xmos rail, it draws 500ma. And 8V on transformer, i wouldn't go lower for that drop.

As for opamp supply, it depends what kind of opamp you use. There is no universal rule for that. From what i see on the market, most discretes will have least distorsions at 15v, but it's neglible if you feed them 12v, so don't stress over it. Read specs of the one you want to utilize, and fashion the supply by it.
There is no place for another psu-1 or 2. I need something small.

Yes, opamps feeds 12V for VA. I use LM6171.
 
@miro1360
I would like to propose a simpler board.
Since the shift register ICs are moved out of the board , there is no need for +-5v to exist on the boards at all.
We could just eliminate it. and use the real estate on the supply board to make a more complex power supply like the Walt jung regulator , which based on the tests provides much better sound.

Although the +/-5v is currently used to power the +/-VL , According to the spec sheet it could be any voltage between +/-5v and +/-12v provided the voltage used for +/-VL is lower than +/-VS. so just using a cap multiplier (or RC filter) to drop the voltage from 12v by about 2 volts would do the trick.

I can help with updating the board design if you are okay to share the source files.

Thanks
Mallik
 
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Shift registers are cheap, and then the choice of input interface is large, USB, SPDIF, TOSLINK, Bluettoth ... to I2S

Let's say this is my cheap experiment, one BT 5.0 module with I2S output and a Pavouk AD1865 DAC. It can also be used with any Miro DAC, all the same. The sound is very decent when using FLAC files, a little less decent with Youtube, Internet radio and the like. It's a pity that BT5.0 does not have lossless transmission.
 

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Actually I don't understand what you mean. Can you give an example of "a different problem" that e.g. XMOS or STM32F7 introduces compared to shift registers? I2S that feeds the shift registers is in most cases generated by these same devices. Generating either I2S or directly PCM is just a change in software and that change in software does not cause any ground bounce.
 
But BB put a digital isolator between the filter and the PCM1702, we need to think about that.
That is crucial + recklocking with already present 4x.xxx MHz MCKs + attenuation of digital input signals before the DAC in the range from specs.
.
Somehow for 300 pages is missing that the JL sounds does have digital ISO, BUT only from XMOS module to CPLD module.