Let me help with these cards, as I have been reading a lot about this, navigating oceans of BS and some very helpful information.
all AUDIOPHONICS DACS I-SABRE ES9023 have the TCXO 0.5ppm clocks and the ES9023 DAC Chip.
v1 has side RCA connector no external screen connectors and optional 5v input with two pin onboard XHP connector. 51Euros
audiophonics.fr/en/diy-dac/a … 10296.html
v2. has back RCA (on top of RASPIs USB and LAN) no external screen connectors and optional 5v input with two pin onboard XHP connector and optional DC Jack for 5 volt DC. 52Euros
audiophonics.fr/en/diy-dac/a … 10176.html
v2.1 has back RCA (on top of RASPIs USB and LAN) WITH external screen connectors and optional 5v input via a special 10pin connector (ATX PSU compatible apparently?) and optional DC Jack for 5 volt DC. 65Euros
audiophonics.fr/en/diy-dac/a … 11917.html
v3 has back RCA (on top of RASPIs USB and LAN) WITH external screen connectors and MANDATORY external 6-7.5v input via DC Jack. This comes as a result of a new presumably better LDO regulator (converts 6/7v to 5v for Raspi power and 3.3 v for the DAC). 76Euros
audiophonics.fr/en/diy-dac/a … 10657.html
I suggest you see this review from a reputable source (not God but clearly knowledgeable and impartial)
youtube.com/watch?v=znJ67VzzlSY
He makes an important point. The DAC converts 0/1 to a 2v signal that our amp will amplify to feed our speakers. If the power supplied to the DAC is shaky that 2v signal produced by the DAC will be bad. So this is why all the “HiFi” DACs have optional (KALI - I Sabre v1 v2 v2.1 - HiFi Berry - Mambo Berry LS DAC+) or mandatory external power connector (I Sabre v3 - Mamboberry HiFi DAC+ [discontinued]). In all cases you only need one power source, the card will feed the Raspi the 5v it needs.
I am not decided yet, but to help others, if you will/or want to spend money on a power supply, i.e. linear power supply or a Ifi wall PSU (volumio.org/product/ifi-ipower/) then v2 should do. If you want to plug chinese wall PSU then it should make sense to spend money on the v3 and presumably better LDO.
I am decided on audiophonics, because the KALI people (a major source of snakeoil salesmanship) convinced me on the importance of a good clock to get accurate sampling of the audio, which the Raspi can not provide. They take the route of 2 clocks (1 for 44.1khz [i.e. CD audio] and one for 48khz modern recordings) resample, buffer and feed the DAC board.
Look at their two clocks
.
The audiophonics take the one clock route. Look at their clock.
Obviously the Audiophonics is more accurate, I do not know by how much, Kali doesn’t give these details, but the TCXO clock misses 1 beat every 2 million (0.5ppm). Regular crystal oscillator move in the 10 - 100ppm range. So although you can’t produce exactly 44.1khz with a 50Khz clock, with clock multipliers you can get better accuracy than with two clocks with higher ppm.
This is my contribution as a “Sunday morning expert” that wants to help other fellow Sunday morning expert get the best bang for their hard earned bucks.