Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter

Hello,

I searched the forum and didn’t find an answer to this question (apologies if I missed it).

My current setup is simple:
RPI 4b + ProtoDAC (TDA1387 x8)
(Running moOde + Roon bridge)
(Power: iFi Power 5V -> RPI -> ProtoDAC via GPIO)

I plan to improve it with:
1-Cleaner power (several options), and
2-FifoPi Q7 reclocker.

Inserting the Q7 between RPI and ProtoDAC requires an adapter with GPIO pins 2-4 removed in order to provide 5V to the DAC, as mentioned earlier on this forum.

So I need 3 clean power sources:
1- 5V to RPI
2- 5V to ProtoDAC
3- 3.3V to Q7

If money (and space) was no object, I could use 3 UcPure packs.

If not, perhaps one UcPure MkIII 5V w parallel DC cables to the RPI and DAC, and one UcPure MkIII 3.3V for the Q7. (Any comments on using parallel - or Y cables?)

If not, then I’m wondering: Where is it the most critical to have clean (no ripple) and highly available (low ESR, high Amperage) power? My guess would be at the DAC, because when the sound signal changes abruptly, the OpAmp needs to be able to feed the I/V stage without being limited by a PS that cannot cope with the sudden current demand.

On the other hand, the RPI’s job is to feed the bit stream to the I2S interface, which is not particularly demanding in terms of Amps, but could still benefit from a really quiet DC source.

If my reasoning is right, I could use my iFi Power 5V on the RPI, and use UcPure packs for the DAC and Q7.

I thank you in advance for your comments!
 
  • Like
Reactions: 1 user
@Trebtek @Gabster 2000 I also have a pretty high tech version of Ian Canada's streamer, including PureStationPi Pro, two LinearPi, three UCconditioners, a FifoPi Q7 and TransportPi AES. It works extremely well with my R2R NOS Lab12 DAC. However, I was curious about the ProtoDAC and I am going to test it against my Lab12 DAC. I am not yet sure where I can place the ProtoDAC inside the streamer box, because it's full with components, but I will sort something out. In terms of power supply, I am thinking of using my 'middle' UCconditioner 5V (see attached photo), which is currently powering the clean side of my StationPi Pro. So, that UCconditioner will hopefully power both the clean side of the StationPi Pro and the ProtoDAC. I hope that should work. Any comments, @hifiamps @Gabster 2000 ?

I also happened to watch Gabi's recent video about using three UFL cables to connect the ProtoDAC with the FifoPi Q7.
That's something I am considering. And if can have the three UFL connections of the FifoPi Q7 connected to the ProtoDAC and the MasterClock of the FifoPi connected to the TransportPi AES, I guess I will be able to run a direct (simultaneous) A-B comparison test between my ProtoDAC and my Lab12 DAC. That would be interesting...
 

Attachments

  • IMG_9998.jpeg
    IMG_9998.jpeg
    451.8 KB · Views: 31
  • IMG_0151 (1).jpeg
    IMG_0151 (1).jpeg
    259.8 KB · Views: 31
  • Like
Reactions: 4 users
@pkonstantinidis
That should work. Love those Jantzen superior caps, also would love to hear you feedback on sound comparison.
Also please Note I did a correction on the order of the I2S signal thanks to Michael as the resistors and the Chip are crossed so
at 13:16 Video should say WS DATA BCK (NOT WS BCK DATA)
If connecting on the Resistor end, like in the video the Correct order is WS DATA BCK as resistors are crosslinked not as per schematic. If you are connecting on the Chip end then the order as per video is correct.
 
  • Like
Reactions: 1 users