IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...

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I recently swapped from the IVSTD to a trafo output stage using Ians board and the Chinese trafos. I seem to have developed a ground loop in doing so.
The build is kind of double insulated in that there is no connection to PE to any of the component inside the (wooden and plastic) box.
I thought I'd try adding a wire from signal ground on the trafo pcb to the PE at the IEC and no change.

Any thoughts. ? I know when I built my brothers Ian Canada streamer using trafo output but not using Ians PCB......I had a ground loop hum when using the CT of the trafo for balanced XLR. Disconnected the CT and used SE rca and all.was.well.
Not as easy to try on Ians board and I am SE.
 
Just finished DDDAC with Ian's Q3 FifoPi board, Neutrino2 clocks, Jensen transformers:
 

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Hello,


I´ve following configuration:
- KHADAS VIM3 (Krescue) + VOLUMIO
- to I2SoverUSBVsIII over USB
- to Ian´s dual mono DAC HAT (using flying wires) + plugged ESS controller

- with passive transformer I/V
- to WHAMMY HPA


I could play DSD up to DSD256 (green LED shows locked DAC).



If I´m trying to play PCM both DAC unlocked: ESS controller shows right values but only clicks to ear.


Automute selection or OSF bypass don´t change anything.



Changes to PC with Audirvana, same results!


So not an software application issue.



Replacing Ian´s dual mono DAC HAT by Chinese single ES9039Q2M DAC and I´ve no problems with playing DSD or PCM: DSD512 and PCM 384kHz.



I don´t know what´s wrong?!


Did someone have an idea what´s the mistake?


Thanks,
JP
 
Hello guys,

problem solved: reducing wire lengths and added wire for 3.3V from pin 1 to pin 17.

Would be very helpfully to have the schematics.

JP

@JP

I'm glad you fixed the issue. For any signals above 1MHz, we have to think them in the RF way. Wire length, grounding, shield and cross talk, impedance matching are all needed to be taken into account.

Regards,
Ian